Finding ID |
Severity |
Title |
Description |
V-205216
|
High |
The DNS server implementation must protect the integrity of transmitted information. |
Without protection of the transmitted information, confidentiality and integrity may be compromised since unprotected communications can be intercepted and either read or altered.
Communication paths outside the physical protection of a controlled boundary are exposed to the possibility of interception and modification. Protecting the confidentiality and integrity of organizational information... |
V-205215
|
High |
The DNS server implementation must utilize cryptographic mechanisms to prevent unauthorized disclosure of non-DNS data stored on the DNS server. |
Applications handling data requiring "data-at-rest" protections must employ cryptographic mechanisms to prevent unauthorized disclosure and modification of the information at rest.
Selection of a cryptographic mechanism is based on the need to protect the confidentiality of organizational information. The strength of mechanism is commensurate with the security category and/or classification... |
V-205214
|
High |
The DNS server implementation must utilize cryptographic mechanisms to prevent unauthorized modification of DNS zone data. |
Applications handling data requiring "data at rest" protections must employ cryptographic mechanisms to prevent unauthorized disclosure and modification of the information at rest.
Selection of a cryptographic mechanism is based on the need to protect the integrity of organizational information. The strength of the mechanism is commensurate with the security... |
V-263646
|
Medium |
The DNS server implementation must compare the internal system clocks on an organization-defined frequency with organization-defined authoritative time source. |
Synchronization of internal system clocks with an authoritative source provides uniformity of time stamps for systems with multiple system clocks and systems connected over a network. |
V-263645
|
Medium |
The DNS server implementation must synchronize system clocks within and between systems or system components. |
Time synchronization of system clocks is essential for the correct execution of many system services, including identification and authentication processes that involve certificates and time-of-day restrictions as part of access control. Denial of service or failure to deny expired credentials may result without properly synchronized clocks within and between systems... |
V-263644
|
Medium |
The DNS server implementation must provide protected storage for cryptographic keys with organization-defined safeguards and/or hardware protected key store. |
A Trusted Platform Module (TPM) is an example of a hardware-protected data store that can be used to protect cryptographic keys. |
V-263643
|
Medium |
The DNS server implementation must include only approved trust anchors in trust stores or certificate stores managed by the organization. |
Public key infrastructure (PKI) certificates are certificates with visibility external to organizational systems and certificates related to the internal operations of systems, such as application-specific time services. In cryptographic systems with a hierarchical structure, a trust anchor is an authoritative source (i.e., a certificate authority) for which trust is assumed... |
V-263642
|
Medium |
The DNS server implementation must protect nonlocal maintenance sessions by separating the maintenance session from other network sessions with the system by logically separated communications paths. |
Nonlocal maintenance and diagnostic activities are conducted by individuals who communicate through either an external or internal network. Communications paths can be logically separated using encryption. |
V-263641
|
Medium |
The DNS server implementation must, for public key-based authentication, implement a local cache of revocation data to support path discovery and validation. |
Public key cryptography is a valid authentication mechanism for individuals, machines, and devices. For PKI solutions, status information for certification paths includes certificate revocation lists or certificate status protocol responses. For PIV cards, certificate validation involves the construction and verification of a certification path to the Common Policy Root trust... |
V-263640
|
Medium |
The DNS server implementation must, for password-based authentication, enforce organization-defined composition and complexity rules. |
Password-based authentication applies to passwords regardless of whether they are used in single-factor or multifactor authentication. Long passwords or passphrases are preferable over shorter passwords. Enforced composition rules provide marginal security benefits while decreasing usability. However, organizations may choose to establish certain rules for password generation (e.g., minimum character length... |
V-263639
|
Medium |
The DNS server implementation must, for password-based authentication, employ automated tools to assist the user in selecting strong password authenticators. |
Password-based authentication applies to passwords regardless of whether they are used in single-factor or multifactor authentication. Long passwords or passphrases are preferable over shorter passwords. Enforced composition rules provide marginal security benefits while decreasing usability. However, organizations may choose to establish certain rules for password generation (e.g., minimum character length... |
V-263638
|
Medium |
The DNS server implementation must, for password-based authentication, allow user selection of long passwords and passphrases, including spaces and all printable characters. |
Password-based authentication applies to passwords regardless of whether they are used in single-factor or multifactor authentication. Long passwords or passphrases are preferable over shorter passwords. Enforced composition rules provide marginal security benefits while decreasing usability. However, organizations may choose to establish certain rules for password generation (e.g., minimum character length... |
V-263637
|
Medium |
The DNS server implementation must, for password-based authentication, require immediate selection of a new password upon account recovery. |
Password-based authentication applies to passwords regardless of whether they are used in single-factor or multifactor authentication. Long passwords or passphrases are preferable over shorter passwords. Enforced composition rules provide marginal security benefits while decreasing usability. However, organizations may choose to establish certain rules for password generation (e.g., minimum character length... |
V-263636
|
Medium |
The DNS server implementation must, for password-based authentication, store passwords using an approved salted key derivation function, preferably using a keyed hash. |
Password-based authentication applies to passwords regardless of whether they are used in single-factor or multifactor authentication. Long passwords or passphrases are preferable over shorter passwords. Enforced composition rules provide marginal security benefits while decreasing usability. However, organizations may choose to establish certain rules for password generation (e.g., minimum character length... |
V-263635
|
Medium |
The DNS server implementation must, for password-based authentication, verify when users create or update passwords, that the passwords are not found on the list of commonly-used, expected, or compromised passwords in IA-5 (1) (a). |
Password-based authentication applies to passwords regardless of whether they are used in single-factor or multifactor authentication. Long passwords or passphrases are preferable over shorter passwords. Enforced composition rules provide marginal security benefits while decreasing usability. However, organizations may choose to establish certain rules for password generation (e.g., minimum character length... |
V-263634
|
Medium |
The DNS server implementation must, for password-based authentication, update the list of passwords when organizational passwords are suspected to have been compromised directly or indirectly. |
Password-based authentication applies to passwords regardless of whether they are used in single-factor or multifactor authentication. Long passwords or passphrases are preferable over shorter passwords. Enforced composition rules provide marginal security benefits while decreasing usability. However, organizations may choose to establish certain rules for password generation (e.g., minimum character length... |
V-263633
|
Medium |
The DNS server implementation must, for password-based authentication, update the list of passwords on an organization-defined frequency. |
Password-based authentication applies to passwords regardless of whether they are used in single-factor or multifactor authentication. Long passwords or passphrases are preferable over shorter passwords. Enforced composition rules provide marginal security benefits while decreasing usability. However, organizations may choose to establish certain rules for password generation (e.g., minimum character length... |
V-263632
|
Medium |
The DNS server implementation must, for password-based authentication, maintain a list of commonly used, expected, or compromised passwords on an organization-defined frequency. |
Password-based authentication applies to passwords regardless of whether they are used in single-factor or multifactor authentication. Long passwords or passphrases are preferable over shorter passwords. Enforced composition rules provide marginal security benefits while decreasing usability. However, organizations may choose to establish certain rules for password generation (e.g., minimum character length... |
V-263631
|
Medium |
The DNS server implementation must implement multifactor authentication for local; network; and/or remote access to privileged accounts; and/or nonprivileged accounts such that the device meets organization-defined strength of mechanism requirements. |
The purpose of requiring a device that is separate from the system to which the user is attempting to gain access for one of the factors during multifactor authentication is to reduce the likelihood of compromising authenticators or credentials stored on the system. Adversaries may be able to compromise such... |
V-263630
|
Medium |
The DNS server implementation must implement multifactor authentication for local; network; and/or remote access to privileged accounts; and/or nonprivileged accounts such that one of the factors is provided by a device separate from the system gaining access. |
The purpose of requiring a device that is separate from the system to which the user is attempting to gain access for one of the factors during multifactor authentication is to reduce the likelihood of compromising authenticators or credentials stored on the system. Adversaries may be able to compromise such... |
V-263629
|
Medium |
The DNS server implementation must require users to be individually authenticated before granting access to the shared accounts or resources. |
Individual authentication prior to shared group authentication mitigates the risk of using group accounts or authenticators. |
V-263628
|
Medium |
The DNS server implementation must prevent the installation of organization-defined software and firmware components without verification that the component has been digitally signed using a certificate that is recognized and approved by the organization. |
Software and firmware components prevented from installation unless signed with recognized and approved certificates include software and firmware version updates, patches, service packs, device drivers, and basic input/output system updates. Organizations can identify applicable software and firmware components by type, by specific items, or a combination of both. Digital signatures... |
V-263627
|
Medium |
The DNS server implementation must automatically generate audit records of the enforcement actions. |
Organizations log system accesses associated with applying configuration changes to ensure that configuration change control is implemented and to support after-the-fact actions should organizations discover any unauthorized changes. |
V-263626
|
Medium |
The DNS server implementation must alert organization-defined personnel or roles upon detection of unauthorized access, modification, or deletion of audit information. |
Audit information includes all information needed to successfully audit system activity, such as audit records, audit log settings, audit reports, and personally identifiable information. Audit logging tools are those programs and devices used to conduct system audit and logging activities. Protection of audit information focuses on technical protection and limits... |
V-263625
|
Medium |
The DNS server implementation must implement the capability to centrally review and analyze audit records from multiple components within the system. |
Automated mechanisms for centralized reviews and analyses include Security Information and Event Management products. |
V-263624
|
Medium |
The DNS server implementation must disable accounts when the accounts are no longer associated to a user. |
Disabling expired, inactive, or otherwise anomalous accounts supports the concepts of least privilege and least functionality, which reduce the attack surface of the system. |
V-263623
|
Medium |
The DNS server implementation must disable accounts when the accounts have expired. |
Disabling expired, inactive, or otherwise anomalous accounts supports the concepts of least privilege and least functionality, which reduce the attack surface of the system. |
V-220317
|
Medium |
All authoritative name servers for a zone must be geographically disbursed. |
In addition to network-based dispersion, authoritative name servers should be dispersed geographically as well. In other words, in addition to being located on different network segments, the authoritative name servers should not all be located within the same building. One approach that some organizations follow is to locate some authoritative... |
V-220316
|
Medium |
A unique TSIG key must be generated for each pair of communicating hosts. |
To enable zone transfer (requests and responses) through authenticated messages, it is necessary to generate a key for every pair of name servers. The key also can be used for securing other transactions, such as dynamic updates, DNS queries, and responses. The binary key string that is generated by most... |
V-205253
|
Medium |
The DNS server implementation must be configured in accordance with the security configuration settings based on DoD security configuration or implementation guidance, including STIGs, NSA configuration guides, CTOs, and DTMs. |
Configuration settings are the set of parameters that can be changed that affect the security posture and/or functionality of the system. Security-related parameters are those parameters impacting the security state of the application, including the parameters required to satisfy other security control requirements.
Configuring the DNS server implementation to follow... |
V-205252
|
Medium |
CNAME records must not point to a zone with lesser security for more than six months. |
The use of CNAME records for exercises, tests, or zone-spanning aliases should be temporary (e.g., to facilitate a migration). When a host name is an alias for a record in another zone, an adversary has two points of attack: the zone in which the alias is defined and the zone... |
V-205251
|
Medium |
A zone file must not include resource records that resolve to a fully qualified domain name residing in another zone. |
If a name server were able to claim authority for a resource record in a domain for which it was not authoritative, this would pose a security risk. In this environment, an adversary could use illicit control of a name server to impact IP address resolution beyond the scope of... |
V-205250
|
Medium |
The private keys corresponding to both the ZSK and the KSK must not be kept on the DNSSEC-aware primary authoritative name server when the name server does not support dynamic updates. |
The private keys in the KSK and ZSK key pairs must be protected from unauthorized access. If possible, the private keys should be stored off-line (with respect to the Internet-facing, DNSSEC-aware name server) in a physically secure, non-network-accessible machine along with the zone file master copy.
This strategy is not... |
V-205249
|
Medium |
The private key corresponding to the ZSK, stored on name servers accepting dynamic updates, must have appropriate directory/file-level access control list-based or cryptography-based protections. |
The private keys in the KSK and ZSK key pairs must be protected from unauthorized access. If possible, the private keys should be stored off-line (with respect to the Internet-facing, DNSSEC-aware name server) in a physically secure, non-network-accessible machine along with the zone file master copy.
This strategy is not... |
V-205248
|
Medium |
The platform on which the name server software is hosted must be configured to send outgoing DNS messages from a random port. |
OS configuration practices as issued by the US Computer Emergency Response Team (US CERT) and the National Institute of Standards and Technology's (NIST's) National Vulnerability Database (NVD), based on identified vulnerabilities that pertain to the application profile into which the name server software fits, should be always followed. In particular,... |
V-205247
|
Medium |
The platform on which the name server software is hosted must be configured to respond to DNS traffic only. |
OS configuration practices as issued by the US Computer Emergency Response Team (US CERT) and the National Institute of Standards and Technology's (NIST's) National Vulnerability Database (NVD), based on identified vulnerabilities that pertain to the application profile into which the name server software fits, should be always followed. In particular,... |
V-205246
|
Medium |
The IP address for hidden master authoritative name servers must not appear in the name servers set in the zone database. |
A hidden master authoritative server is an authoritative DNS server whose IP address does not appear in the name server set for a zone. All of the name servers that do appear in the zone database as designated name servers get their zone data from the hidden master via a... |
V-205245
|
Medium |
The DNS Name Server software must run with restricted privileges. |
Failure to provide logical access restrictions associated with changes to application configuration may have significant effects on the overall security of the system. When dealing with access restrictions pertaining to change control, it should be noted that any changes to the hardware, software, and/or firmware components of the information system... |
V-205244
|
Medium |
The DNS name server software must be at the latest version. |
Each newer version of the name server software, especially the BIND software, generally is devoid of vulnerabilities found in earlier versions because it has design changes incorporated to take care of those vulnerabilities. These vulnerabilities have been exploited (i.e., some form of attack was launched), and sufficient information has been... |
V-205243
|
Medium |
The DNS must utilize valid root name servers in the local root zone file. |
All caching name servers must be authoritative for the root zone because, without this starting point, they would have no knowledge of the DNS infrastructure and thus would be unable to respond to any queries. The security risk is that an adversary could change the root hints and direct the... |
V-205242
|
Medium |
The DNS implementation must implement internal/external role separation. |
DNS servers with an internal role only process name/address resolution requests from within the organization (i.e., internal clients). DNS servers with an external role only process name/address resolution information requests from clients external to the organization (i.e., on the external networks, including the Internet). The set of clients that can... |
V-205241
|
Medium |
The DNS implementation must enforce a Discretionary Access Control (DAC) policy that limits propagation of access rights. |
Discretionary Access Control (DAC) is based on the premise that individual users are "owners" of objects and therefore have discretion over who should be authorized to access the object and in which mode (e.g., read or write). Ownership is usually acquired as a consequence of creating the object or via... |
V-205240
|
Medium |
The DNS implementation must be conformant to the IETF DNS specification. |
Any DNS implementation must be designed to be able to conform to the Internet Engineering Task Force (IETF) specification. DoD utilizes many different DNS servers, and it is essential that core capabilities of all are compatible. DNS servers that do not provide services compliant to the DNS RFCs may cause... |
V-205239
|
Medium |
Primary authoritative name servers must be configured to only receive zone transfer requests from specified secondary name servers. |
Authoritative name servers (especially primary name servers) should be configured with an allow-transfer access control substatement designating the list of hosts from which zone transfer requests can be accepted. These restrictions address the denial-of-service threat and potential exploits from unrestricted dissemination of information about internal resources. Based on the need-to-know,... |
V-205238
|
Medium |
In a split DNS configuration, where separate name servers are used between the external and internal networks, the internal name server must be configured to not be reachable from outside resolvers. |
Instead of having the same set of authoritative name servers serve different types of clients, an enterprise could have two different sets of authoritative name servers.
One set, called external name servers, can be located within a DMZ; these would be the only name servers that are accessible to external... |
V-205237
|
Medium |
In a split DNS configuration, where separate name servers are used between the external and internal networks, the external name server must be configured to not be reachable from inside resolvers. |
Instead of having the same set of authoritative name servers serve different types of clients, an enterprise could have two different sets of authoritative name servers.
One set, called external name servers, can be located within a DMZ; these would be the only name servers that are accessible to external... |
V-205236
|
Medium |
For zones split between the external and internal sides of a network, the RRs for the external hosts must be separate from the RRs for the internal hosts. |
Authoritative name servers for an enterprise may be configured to receive requests from both external and internal clients.
External clients need to receive RRs that pertain only to public services (public Web server, mail server, etc.)
Internal clients need to receive RRs pertaining to public services as well as internal... |
V-205235
|
Medium |
Digital signature algorithm used for DNSSEC-enabled zones must be FIPS-compatible. |
The choice of digital signature algorithm will be based on recommended algorithms in well-known standards. NIST's Digital Signature Standard (DSS) [FIPS186] provides three algorithm choices:
* Digital Signature Algorithm (DSA)
* RSA
* Elliptic Curve DSA (ECDSA).
Of these three algorithms, RSA and DSA are more widely available and hence... |
V-205234
|
Medium |
An authoritative name server must be configured to enable DNSSEC Resource Records. |
The specification for a digital signature mechanism in the context of the DNS infrastructure is in IETF's DNSSEC standard. In DNSSEC, trust in the public key (for signature verification) of the source is established not by going to a third party or a chain of third parties (as in public... |
V-205233
|
Medium |
All authoritative name servers for a zone must have the same version of zone information. |
The only protection approach for content control of DNS zone file is the use of a zone file integrity checker. The effectiveness of integrity checking using a zone file integrity checker depends upon the database of constraints built into the checker. The deployment process consists of developing these constraints with... |
V-205232
|
Medium |
All authoritative name servers for a zone must be located on different network segments. |
Most enterprises have an authoritative primary server and a host of authoritative secondary name servers. It is essential that these authoritative name servers for an enterprise be located on different network segments. This dispersion ensures the availability of an authoritative name server not only in situations in which a particular... |
V-205231
|
Medium |
The two files generated by the dnssec-keygen program must be made accessible only to the server administrator account, or deleted, after they have been copied to the key file in the name server. |
To enable zone transfer (requests and responses) through authenticated messages, it is necessary to generate a key for every pair of name servers. The key also can be used for securing other transactions, such as dynamic updates, DNS queries, and responses. The binary key string that is generated by most... |
V-205230
|
Medium |
The DNS implementation must ensure each NS record in a zone file points to an active name server authoritative for the domain specified in that record. |
Poorly constructed NS records pose a security risk because they create conditions under which an adversary might be able to provide the missing authoritative name services that are improperly specified in the zone file. The adversary could issue bogus responses to queries that clients would accept because they learned of... |
V-205229
|
Medium |
NSEC3 must be used for all internal DNS zones. |
To ensure that RRs associated with a query are really missing in a zone file and have not been removed in transit, the DNSSEC mechanism provides a means for authenticating the nonexistence of an RR. It generates a special RR called an NSEC (or NSEC3) RR that lists the RRTypes... |
V-205228
|
Medium |
The validity period for the RRSIGs covering a zones DNSKEY RRSet must be no less than two days and no more than one week. |
The best way for a zone administrator to minimize the impact of a key compromise is by limiting the validity period of RRSIGs in the zone and in the parent zone. This strategy limits the time during which an attacker can take advantage of a compromised key to forge responses.... |
V-205227
|
Medium |
The salt value for zones signed using NSEC3 RRs must be changed every time the zone is completely re-signed. |
NSEC3 RRs contain other options than just the (hashed) next name and RRType bitmap. There are also 2 values associated with the NSEC3 RR: the iterations (number of times each name is hashed) and the salt (string appended to each name before hashing). These values are configurable during signing and... |
V-205226
|
Medium |
The DNS server must implement NIST FIPS-validated cryptography for provisioning digital signatures, generating cryptographic hashes, and protecting unclassified information requiring confidentiality. |
Use of weak or untested encryption algorithms undermines the purposes of utilizing encryption to protect data. The application must implement cryptographic modules adhering to the higher standards approved by the federal government since this provides assurance they have been tested and validated. |
V-205225
|
Medium |
The DNS implementation must generate audit records for the success and failure of all name server events. |
Auditing and logging are key components of any security architecture. It is essential for security personnel to know what is being performed on the system, where an event occurred, when an event occurred, and by whom the event was triggered, in order to compile an accurate risk assessment. Logging the... |
V-205224
|
Medium |
The DNS implementation must generate audit records for the success and failure of start and stop of the name server service or daemon. |
Auditing and logging are key components of any security architecture. It is essential for security personnel to know what is being performed on the system, where an event occurred, when an event occurred, and by whom the event was triggered, in order to compile an accurate risk assessment. Logging the... |
V-205223
|
Medium |
The DNS server implementation must log the event and notify the system administrator when anomalies in the operation of the signed zone transfers are discovered. |
Security function is defined as the hardware, software, and/or firmware of the information system responsible for enforcing the system security policy and supporting the isolation of code and data on which the protection is based. Security functionality includes, but is not limited to, establishing system accounts, configuring access authorizations (i.e.,... |
V-205222
|
Medium |
The DNS server implementation must perform verification of the correct operation of security functions: upon system start-up and/or restart; upon command by a user with privileged access; and/or every 30 days. |
Security function is defined as the hardware, software, and/or firmware of the information system responsible for enforcing the system security policy and supporting the isolation of code and data on which the protection is based. Security functionality includes, but is not limited to, establishing system accounts, configuring access authorizations (i.e.,... |
V-205221
|
Medium |
The DNS server implementation must follow procedures to re-role a secondary name server as the master name server should the master name server permanently lose functionality. |
Failing to an unsecure condition negatively impacts application security and can lead to system compromise. Failure conditions include, for example, loss of communications among critical system components or between system components and operational facilities. Fail-safe procedures include, for example, alerting operator personnel and providing specific instructions on subsequent steps to... |
V-205220
|
Medium |
The DNS server implementation must behave in a predictable and documented manner that reflects organizational and system objectives when invalid inputs are received. |
A common vulnerability of applications is unpredictable behavior when invalid inputs are received. This requirement guards against adverse or unintended system behavior caused by invalid inputs, where information system responses to the invalid input may be disruptive or cause the system to fail into an unsafe state. The behavior will... |
V-205219
|
Medium |
The DNS server implementation must maintain the integrity of information during reception. |
Information can be either unintentionally or maliciously disclosed or modified during reception, including, for example, during aggregation, at protocol transformation points, and during packing/unpacking. These unauthorized disclosures or modifications compromise the confidentiality or integrity of the information.
Confidentiality is not an objective of DNS, but integrity is. DNS is responsible... |
V-205218
|
Medium |
The DNS server implementation must maintain the integrity of information during preparation for transmission. |
Information can be either unintentionally or maliciously disclosed or modified during preparation for transmission, including, for example, during aggregation, at protocol transformation points, and during packing/unpacking. These unauthorized disclosures or modifications compromise the confidentiality or integrity of the information.
Confidentiality is not an objective of DNS, but integrity is. DNS... |
V-205217
|
Medium |
The DNS server implementation must implement cryptographic mechanisms to detect changes to information during transmission unless otherwise protected by alternative physical safeguards, such as, at a minimum, a Protected Distribution System (PDS). |
Encrypting information for transmission protects information from unauthorized disclosure and modification. Cryptographic mechanisms implemented to protect information integrity include, for example, cryptographic hash functions which have common application in digital signatures, checksums, and message authentication codes.
Confidentiality is not an objective of DNS, but integrity is. DNSSEC and TSIG/SIG(0) both... |
V-205213
|
Medium |
If the DNS server is using SIG(0), the DNS server implementation must only allow the use of DoD PKI-established certificate authorities for verification of the establishment of protected transactions. |
Untrusted Certificate Authorities (CA) can issue certificates, but they may be issued by organizations or individuals that seek to compromise DoD systems or by organizations with insufficient security controls. If the CA used for verifying the certificate is not a DoD-approved CA, trust of this CA has not been established.... |
V-205212
|
Medium |
A DNS server implementation must perform data origin verification authentication on the name/address resolution responses the system receives from authoritative sources. |
If data origin authentication and data integrity verification are not performed, the resultant response could be forged, it may have come from a poisoned cache, the packets could have been intercepted without the resolver's knowledge, or resource records could have been removed which would result in query failure or denial... |
V-205211
|
Medium |
A DNS server implementation must perform data integrity verification on the name/address resolution responses the system receives from authoritative sources. |
If data origin authentication and data integrity verification are not performed, the resultant response could be forged, it may have come from a poisoned cache, the packets could have been intercepted without the resolver's knowledge, or resource records could have been removed that would result in query failure or denial... |
V-205210
|
Medium |
A DNS server implementation must request data integrity verification on the name/address resolution responses the system receives from authoritative sources. |
If data origin authentication and data integrity verification are not performed, the resultant response could be forged, it may have come from a poisoned cache, the packets could have been intercepted without the resolver's knowledge, or resource records could have been removed that would result in query failure or denial... |
V-205209
|
Medium |
A DNS server implementation must request data origin authentication verification on the name/address resolution responses the system receives from authoritative sources. |
If data origin authentication and data integrity verification are not performed, the resultant response could be forged, it may have come from a poisoned cache, the packets could have been intercepted without the resolver's knowledge, or resource records could have been removed that would result in query failure or denial... |
V-205208
|
Medium |
A DNS server implementation must provide additional integrity artifacts along with the authoritative name resolution data the system returns in response to external name/address resolution queries. |
The major threat associated with DNS forged responses or failures is the integrity of the DNS data returned in the response. The principle of DNSSEC is to mitigate this threat by providing data origin authentication, establishing trust in the source. This requirement enables remote clients to obtain origin authentication and... |
V-205207
|
Medium |
A DNS server implementation must provide data integrity protection artifacts for internal name/address resolution queries. |
The major threat associated with DNS forged responses or failures is the integrity of the DNS data returned in the response. The principle of DNSSEC is to mitigate this threat by providing data origin authentication, establishing trust in the source. This requirement enables remote clients to obtain origin authentication and... |
V-205206
|
Medium |
A DNS server implementation must provide data origin artifacts for internal name/address resolution queries. |
The major threat associated with DNS forged responses or failures is the integrity of the DNS data returned in the response. The principle of DNSSEC is to mitigate this threat by providing data origin authentication, establishing trust in the source. This requirement enables remote clients to obtain origin authentication and... |
V-205205
|
Medium |
The DNS server implementation, for PKI-based authentication, must implement a local cache of revocation data to support path discovery and validation in case of the inability to access revocation information via the network. |
Without configuring a local cache of revocation data, there is the potential to allow access to users who are no longer authorized (users with revoked certificates).
SIG(0) is used for server-to-server authentication for DNS transactions, and it uses PKI-based authentication. So, in cases where SIG(0) is being used instead of... |
V-205204
|
Medium |
The DNS server implementation must authenticate another DNS server before establishing a remote and/or network connection using bidirectional authentication that is cryptographically based. |
Without authenticating devices, unidentified or unknown devices may be introduced, thereby facilitating malicious activity. Bidirectional authentication provides stronger safeguards to validate the identity of other devices for connections that are of greater risk.
This requirement applies to server-to-server (zone transfer) transactions only and is provided by TSIG/SIG(0), which enforces mutual... |
V-205203
|
Medium |
The DNS server implementation must authenticate the other DNS server before responding to a server-to-server transaction. |
Without authenticating devices, unidentified or unknown devices may be introduced, thereby facilitating malicious activity. Device authentication is a solution enabling an organization to manage devices. It is an additional layer of authentication ensuring only specific pre-authorized devices can access the system.
This requirement applies to server-to-server (zone transfer) transactions only... |
V-205201
|
Medium |
The DNS implementation must prohibit recursion on authoritative name servers. |
A potential vulnerability of DNS is that an attacker can poison a name server's cache by sending queries that will cause the server to obtain host-to-IP address mappings from bogus name servers that respond with incorrect information. Once a name server has been poisoned, legitimate clients may be directed to... |
V-205199
|
Medium |
In the event of an error when validating the binding of another DNS servers identity to the DNS information, the DNS server implementation must log the event and send notification to the DNS administrator. |
Failing to act on the validation errors may result in the use of invalid, corrupted, or compromised information. The validation of bindings can be achieved, for example, by the use of cryptographic checksums. Validations must be performed automatically.
At a minimum, the application must log the validation error. However, more... |
V-205198
|
Medium |
The DNS server implementation must validate the binding of the other DNS servers identity to the DNS information for a server-to-server transaction (e.g., zone transfer). |
Validation of the binding of the information prevents the modification of information between production and review. The validation of bindings can be achieved, for example, by the use of cryptographic checksums. Validations must be performed automatically.
DNSSEC and TSIG/SIG(0) technologies are not effective unless the digital signatures they generate are... |
V-205197
|
Medium |
The DNS server implementation must provide the means for authorized individuals to determine the identity of the source of the DNS server-provided information. |
Without a means for identifying the individual that produced the information, the information cannot be relied upon. Identifying the validity of information may be delayed or deterred.
This requirement provides organizational personnel with the means to identify who produced specific information in the event of an information transfer. DNSSEC and... |
V-205196
|
Medium |
The DNS server implementation must strongly bind the identity of the DNS server with the DNS information. |
Weakly bound credentials can be modified without invalidating the credential; therefore, non-repudiation can be violated.
This requirement supports audit requirements that provide organizational personnel with the means to identify who produced specific information in the event of an information transfer. Organizations and/or data owners determine and approve the strength of... |
V-205193
|
Medium |
The DNS server implementation must be configured to generate audit records for failed security verification tests so that the ISSO and ISSM can be notified of the failures. |
Security function is defined as the hardware, software, and/or firmware of the information system responsible for enforcing the system security policy and supporting the isolation of code and data on which the protection is based. Security functionality includes, but is not limited to, establishing system accounts, configuring access authorizations (i.e.,... |
V-205192
|
Medium |
The DNS server implementation must, when a component failure is detected, activate a notification to the system administrator. |
Predictable failure prevention requires organizational planning to address system failure issues. If components key to maintaining systems security fail to function, the system could continue operating in an insecure state. The organization must be prepared and the application must support requirements that specify if the application must alarm for such... |
V-205191
|
Medium |
The DNS server implementation must check the validity of all data inputs except those specifically identified by the organization. |
Invalid user input occurs when a user inserts data or characters into an application's data entry fields and the application is unprepared to process that data. This results in unanticipated application behavior, potentially leading to an application or information system compromise. Invalid input is one of the primary methods employed... |
V-205190
|
Medium |
The DNS server implementation must manage excess capacity, bandwidth, or other redundancy to limit the effects of information flooding types of Denial of Service (DoS) attacks. |
A DoS is a condition when a resource is not available for legitimate users. When this occurs, the organization either cannot accomplish its mission or must operate at degraded capacity.
In the case of application DoS attacks, care must be taken when designing the application to ensure the application makes... |
V-205189
|
Medium |
The DNS server implementation must restrict the ability of individuals to use the DNS server to launch Denial of Service (DoS) attacks against other information systems. |
A DoS is a condition where a resource is not available for legitimate users. When this occurs, the organization either cannot accomplish its mission or must operate at degraded capacity. Individuals of concern can include hostile insiders or external adversaries that have successfully breached the information system and are using... |
V-205188
|
Medium |
The DNS server implementation must prevent unauthorized and unintended information transfer via shared system resources. |
Preventing unauthorized information transfers mitigates the risk of information, including encrypted representations of information, produced by the actions of prior users/roles (or the actions of processes acting on behalf of prior users/roles) from being available to any current users/roles (or current processes) that obtain access to shared system resources (e.g.,... |
V-205187
|
Medium |
The DNS server implementation must protect the confidentiality and integrity of secret/private cryptographic keys at rest and the integrity of DNS information at rest. |
Information at rest refers to the state of information when it is located on a secondary storage device within an organizational information system. Mobile devices, laptops, desktops, and storage devices can be either lost or stolen, and the contents of their data storage (e.g., hard drives and non-volatile memory) can... |
V-205186
|
Medium |
In the event of a system failure, the DNS server implementation must preserve any information necessary to determine cause of failure and any information necessary to return to operations with least disruption to mission processes. |
Failure to a known state can address safety or security in accordance with the mission/business needs of the organization. Failure to a known secure state helps prevent a loss of confidentiality, integrity, or availability in the event of a failure of the information system or a component of the system.... |
V-205185
|
Medium |
The DNS server implementation must fail to a secure state if system initialization fails, shutdown fails, or aborts fail. |
Failure to a known safe state helps prevent systems from failing to a state that may cause loss of data or unauthorized access to system resources. Applications or systems that fail suddenly and with no incorporated failure state planning may leave the hosting system available but with a reduced security... |
V-205184
|
Medium |
The DNS implementation must protect the authenticity of communications sessions for queries. |
The underlying feature in the major threat associated with DNS query/response (i.e., forged response or response failure) is the integrity of DNS data returned in the response. An integral part of integrity verification is to ensure that valid data has originated from the right source. DNSSEC is required for securing... |
V-205183
|
Medium |
The DNS implementation must protect the authenticity of communications sessions for dynamic updates. |
DNS is a fundamental network service that is prone to various attacks, such as cache poisoning and man-in-the middle attacks. If communication sessions are not provided appropriate validity protections, such as the employment of DNSSEC, the authenticity of the data cannot be guaranteed. |
V-205182
|
Medium |
The DNS implementation must protect the authenticity of communications sessions for zone transfers. |
DNS is a fundamental network service that is prone to various attacks, such as cache poisoning and man-in-the middle attacks.
If communication sessions are not provided appropriate validity protections, such as the employment of DNSSEC, the authenticity of the data cannot be guaranteed. |
V-205180
|
Medium |
A DNS server implementation must provide the means to enable verification of a chain of trust among parent and child domains (if the child supports secure resolution services). |
If name server replies are invalid or cannot be validated, many networking functions and communication would be adversely affected. With DNS, the presence of Delegation Signer (DS) records associated with child zones informs clients of the security status of child zones. These records are crucial to the DNSSEC chain of... |
V-205179
|
Medium |
The DNS server implementation must enforce approved authorizations for controlling the flow of information between DNS servers and between DNS servers and DNS clients based on DNSSEC policies. |
A mechanism to detect and prevent unauthorized communication flow must be configured or provided as part of the system design. If information flow is not enforced based on approved authorizations, the system may become compromised. Information flow control regulates where information is allowed to travel within a system and between... |
V-205178
|
Medium |
The validity period for the RRSIGs covering the DS RR for a zones delegated children must be no less than two days and no more than one week. |
The best way for a zone administrator to minimize the impact of a key compromise is by limiting the validity period of RRSIGs in the zone and in the parent zone. This strategy limits the time during which an attacker can take advantage of a compromised key to forge responses.... |
V-205177
|
Medium |
A DNS server implementation must provide the means to indicate the security status of child zones. |
If name server replies are invalid or cannot be validated, many networking functions and communication would be adversely affected. With DNS, the presence of Delegation Signer (DS) records associated with child zones informs clients of the security status of child zones. These records are crucial to the DNSSEC chain of... |
V-205176
|
Medium |
A DNS server implementation must provide additional data origin artifacts along with the authoritative data the system returns in response to external name/address resolution queries. |
The underlying feature in the major threat associated with DNS query/response (i.e., forged response or response failure) is the integrity of DNS data returned in the response. The security objective is to verify the integrity of each response received. An integral part of integrity verification is to ensure that valid... |
V-205175
|
Medium |
The DNS server implementation must employ strong authenticators in the establishment of nonlocal maintenance and diagnostic sessions. |
If maintenance tools are used by unauthorized personnel, they may accidentally or intentionally damage or compromise the system. The act of managing systems and applications includes the ability to access sensitive application information, such as system configuration details, diagnostic information, user information, and potentially sensitive application data.
Nonlocal maintenance and... |
V-205174
|
Medium |
Signature generation using the KSK must be done off-line, using the KSK-private stored off-line. |
Security-relevant information is any information within information systems that can potentially impact the operation of security functions or the provision of security services in a manner that could result in failure to enforce system security policies or maintain the isolation of code and data.
Security-relevant information includes, for example, file... |
V-205173
|
Medium |
Only the private key corresponding to the ZSK alone must be kept on the name server that does support dynamic updates. |
The private keys in the KSK and ZSK key pairs must be protected from unauthorized access. If possible, the private keys should be stored off-line (with respect to the Internet-facing, DNSSEC-aware name server) in a physically secure, non-network-accessible machine along with the zone file master copy.
This strategy is not... |
V-205172
|
Medium |
Read/Write access to the key file must be restricted to the account that runs the name server software only. |
To enable zone transfer (requests and responses) through authenticated messages, it is necessary to generate a key for every pair of name servers. The key can also be used for securing other transactions, such as dynamic updates, DNS queries, and responses. The binary key string that is generated by most... |
V-205171
|
Medium |
The key file must be owned by the account under which the name server software is run. |
To enable zone transfer (requests and responses) through authenticated messages, it is necessary to generate a key for every pair of name servers. The key can also be used for securing other transactions, such as dynamic updates, DNS queries, and responses. The binary key string that is generated by most... |
V-205170
|
Medium |
The DNS server implementation, when using PKI-based authentication, must enforce authorized access to the corresponding private key. |
The cornerstone of the PKI is the private key used to encrypt or digitally sign information. If the private key is stolen, this will lead to the compromise of the authentication and non-repudiation gained through PKI because the attacker can use the private key to digitally sign documents and pretend... |
V-205169
|
Medium |
The DNS server implementation must uniquely identify the other DNS server before responding to a server-to-server transaction. |
Without identifying devices, unidentified or unknown devices may be introduced, thereby facilitating malicious activity. This applies to server-to-server (zone transfer) transactions only and is provided by TSIG/SIG(0), which enforces mutual server authentication using a key that is unique to each server pair (TSIG) or using PKI-based authentication (SIG(0)), thus uniquely... |
V-205168
|
Medium |
The DNS server implementation must be configured to prohibit or restrict unapproved ports and protocols. |
In order to prevent unauthorized connection of devices, unauthorized transfer of information, or unauthorized tunneling (i.e., embedding of data types within data types), organizations must disable or restrict unused or unnecessary physical and logical ports/protocols on information systems.
Applications are capable of providing a wide variety of functions and services.... |
V-205167
|
Medium |
The DNS server implementations audit records must be backed up at least every seven days onto a different system or system component than the system or component being audited. |
Protection of log data includes assuring log data is not accidentally lost or deleted. Backing up audit records to a different system or onto separate media than the system being audited on a defined frequency helps to assure, in the event of a catastrophic system failure, the audit records will... |
V-205166
|
Medium |
The DNS server implementation must generate audit records containing information that establishes the identity of any individual or process associated with the event. |
Without information that establishes the identity of the subjects (i.e., users or processes acting on behalf of users) associated with the events, security personnel cannot determine responsibility for the potentially harmful event.
Event identifiers (if authenticated or otherwise known) include, but are not limited to, user database tables, primary key... |
V-205165
|
Medium |
The DNS server implementation must produce audit records that contain information to establish the outcome of the events. |
Without information about the outcome of events, security personnel cannot make an accurate assessment about whether an attack was successful or if changes were made to the security state of the system.
Event outcomes can include indicators of event success or failure and event-specific results (e.g., the security state of... |
V-205164
|
Medium |
The DNS server implementation must produce audit records containing information to establish the source of the events. |
Without establishing the source of the event, it is impossible to establish, correlate, and investigate the events leading up to an outage or attack. Associating information about the source of the event within the application provides a means of investigating an attack, recognizing resource utilization or capacity thresholds, or identifying... |
V-205163
|
Medium |
The DNS server implementation must produce audit records containing information to establish where the events occurred. |
Without establishing where events occurred, it is impossible to establish, correlate, and investigate the events relating to an incident. Associating information about where the event occurred within the application provides a means of investigating an attack, recognizing resource utilization or capacity thresholds, or identifying an improperly configured application. In order... |
V-205162
|
Medium |
The DNS server implementation must produce audit records containing information to establish when (date and time) the events occurred. |
Without establishing when events occurred, it is impossible to establish, correlate, and investigate the events relating to an incident.
Associating event types with detected events in the application and audit logs provides a means of investigating an attack, recognizing resource utilization or capacity thresholds, or identifying an improperly configured application.... |
V-205161
|
Medium |
The DNS server implementation must produce audit records containing information to establish what type of events occurred. |
Auditing and logging are key components of any security architecture. It is essential for security personnel to know what is being performed on the system, where an event occurred, when an event occurred, and by whom the event was triggered, in order to compile an accurate risk assessment. Logging the... |
V-205160
|
Medium |
The DNS server implementation must be configured to provide audit record generation capability for DoD-defined auditable events within all DNS server components. |
Without the capability to generate audit records, it would be difficult to establish, correlate, and investigate the events relating to an incident, or identify those responsible for one. The actual auditing is performed by the OS/NDM, but the configuration to trigger the auditing is controlled by the DNS server.
The... |
V-205159
|
Medium |
The DNS server implementation must be configured to provide audit record generation capability for DoD-defined auditable events within all DNS server components. |
Without the capability to generate audit records, it would be difficult to establish, correlate, and investigate the events relating to an incident, or identify those responsible for one. The actual auditing is performed by the OS/NDM, but the configuration to trigger the auditing is controlled by the DNS server.
The... |
V-205158
|
Medium |
The DNS implementation must limit the number of concurrent sessions client connections to the number of allowed dynamic update clients. |
Limiting the number of concurrent sessions reduces the risk of Denial of Service (DoS) to the DNS implementation.
Name servers do not have direct user connections but accept client connections for queries. Original restriction on client connections should be high enough to prevent a self-imposed denial of service, after which... |
V-205157
|
Medium |
The DNS implementation must limit the number of concurrent sessions for zone transfers to the number of secondary name servers. |
Limiting the number of concurrent sessions reduces the risk of Denial of Service (DoS) to the DNS implementation.
Name servers do not have direct user connections but accept client connections for queries. Original restriction on client connections should be high enough to prevent a self-imposed denial of service, after which... |