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... |
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:
*... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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),... |
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),... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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,... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
V-205202 | Medium | The DNS server implementation must require devices to re-authenticate for each zone transfer and dynamic update request connection attempt. | Without re-authenticating devices, unidentified or unknown devices may be introduced, thereby facilitating malicious activity.
In addition to the re-authentication requirements associated with... |
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... |
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... |
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,... |
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... |
V-205215 | Medium | 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... |
V-205214 | Medium | 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... |
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... |
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... |
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... |
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... |
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... |
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... |
V-205194 | Medium | The DNS Name Server software must be configured to refuse queries for its version information. | 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... |
V-205195 | Medium | The HINFO, RP, TXT and LOC RR types must not be used in the zone SOA. | There are several types of RRs in the DNS that are meant to convey information to humans and applications about the network, hosts, or services. These RRs include the Responsible Person (RP)... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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,... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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... |
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. ... |
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... |
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... |
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,... |
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... |
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... |
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... |
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... |
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... |