| Finding ID |
Severity |
Title |
Description |
|
V-259710
|
High |
The application must protect the confidentiality and 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.
This requirement applies only to those applications that are either distributed or can allow access to data nonlocally. Use of this requirement will be limited to situations... |
|
V-259686
|
High |
Exchange servers must have an approved DOD email-aware virus protection software installed. |
With the proliferation of trojans, viruses, and spam attaching themselves to email messages (or attachments), it is necessary to have capable email-aware antivirus (AV) products to scan messages and identify any resident malware. Because email messages and their attachments are formatted to the MIME standard, a flat-file AV scanning engine... |
|
V-259712
|
Medium |
Exchange 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. |
Configuring Exchange to implement organization-wide security implementation guides and security checklists ensures compliance with federal standards and establishes a common security baseline across DOD that reflects the most restrictive security posture consistent with operational requirements.
Configuration settings are the set of parameters that can be changed that affect the security... |
|
V-259711
|
Medium |
Exchange must have the most current, approved Cumulative Update installed. |
Failure to install the most current Exchange Cumulative Update (CU) leaves a system vulnerable to exploitation. Current CUs correct known security and system vulnerabilities. |
|
V-259709
|
Medium |
Exchange must provide mailbox databases in a highly available and redundant configuration. |
Exchange Server mailbox databases and any data contained in those mailboxes should be protected. This can be accomplished by configuring Mailbox servers and databases for high availability and site resilience.
A database availability group (DAG) is a component of the Mailbox server high availability and site resilience framework built into... |
|
V-259708
|
Medium |
Exchange internal send connectors must use an authentication level. |
The Simple Mail Transfer Protocol (SMTP) connector is used by Exchange to send and receive messages from server to server. Several controls work together to provide security between internal servers. This setting controls the encryption method used for communications between servers. With this feature enabled, only servers capable of supporting... |
|
V-259707
|
Medium |
The Exchange SMTP automated banner response must not reveal server details. |
Automated connection responses occur as a result of FTP or Telnet connections when connecting to those services. They report a successful connection by greeting the connecting client and stating the name, release level, and (often) additional information regarding the responding product. While useful to the connecting client, connection responses can... |
|
V-259706
|
Medium |
Exchange must not send nondelivery reports to remote domains. |
Attackers can use automated messages to determine whether a user account is active, in the office, traveling, and so on. An attacker might use this information to conduct future attacks. Ensure that nondelivery reports to remote domains are disabled. Before enabling this setting, first configure a remote domain using the... |
|
V-259705
|
Medium |
Exchange must not send delivery reports to remote domains. |
Attackers can use automated messages to determine whether a user account is active, in the office, traveling, and so on. An attacker might use this information to conduct future attacks. Ensure that delivery reports to remote domains are disabled. Before enabling this setting, first configure a remote domain using the... |
|
V-259704
|
Medium |
The Exchange email application must not share a partition with another application. |
In the same way that added security layers can provide a cumulative positive effect on security posture, multiple applications can provide a cumulative negative effect. A vulnerability and subsequent exploit to one application can lead to an exploit of other applications sharing the same security context. For example, an exploit... |
|
V-259703
|
Medium |
Exchange Outlook Anywhere clients must use NTLM authentication to access email. |
Identification and authentication provide the foundation for access control. Access to email services applications require NTLM authentication. Outlook Anywhere, if authorized for use by the site, must use NTLM authentication when accessing email.
Note: There is a technical restriction in Exchange Outlook Anywhere that requires a direct SSL connection from... |
|
V-259702
|
Medium |
Exchange services must be documented, and unnecessary services must be removed or disabled. |
Unneeded but running services offer attackers an enhanced attack profile, and attackers are constantly watching to discover open ports with running services. By analyzing and disabling unneeded services, the associated open ports become unresponsive to outside queries, and servers become more secure as a result.
Exchange Server has role-based server... |
|
V-259701
|
Medium |
Exchange software must be monitored for unauthorized changes. |
Monitoring software files for changes against a baseline on a regular basis may help detect the possible introduction of malicious code on a system. |
|
V-259700
|
Medium |
An Exchange software baseline copy must exist. |
Exchange software, as with other application software installed on a host system, must be included in a system baseline record and periodically reviewed; otherwise, unauthorized changes to the software may not be discovered. This effort is a vital step to securing the host and the applications, as it is the... |
|
V-259699
|
Medium |
The Exchange application directory must be protected from unauthorized access. |
Default product installations may provide more generous access permissions than are necessary to run the application. By examining and tailoring access permissions to provide the least amount of privilege possible more closely, attack vectors that align with user permissions are less likely to access more highly secured areas. |
|
V-259698
|
Medium |
Role-Based Access Control must be defined for privileged and nonprivileged users. |
Role Based Access Control (RBAC) is the permissions model used in Microsoft Exchange Server 2013, 2016, and 2019. With RBAC, there is no need to modify and manage access control lists (ACLs), which was done in Exchange Server 2007. ACLs created several challenges in Exchange 2007, such as modifying ACLs... |
|
V-259695
|
Medium |
The Exchange malware scanning agent must be configured for automatic updates. |
Antimalware protection in Exchange Server 2019 helps combat viruses and spyware in an email messaging environment. Viruses infect other programs and data, and they spread throughout computer looking for programs to infect. Spyware gathers personal information (for example, sign-in information and personal data) and sends it back to its author.... |
|
V-259694
|
Medium |
Exchange antimalware agent must be enabled and configured. |
Microsoft Exchange 2019 offers built-in antimalware protection for messages going through the transport pipeline. When enabled, the default settings are configured to automatically update.
Exchange's built-in Malware Agent is not designed to address all malicious code protection workloads. This workload is best handled by third-party antivirus and intrusion prevention software.... |
|
V-259692
|
Medium |
Exchange must not send automated replies to remote domains. |
Attackers can use automated messages to determine whether a user account is active, in the office, traveling, and so on. An attacker might use this information to conduct future attacks. Remote users will not receive automated "Out of Office" delivery reports. This setting can be used to determine if all... |
|
V-259691
|
Medium |
Exchange must have anti-spam filtering configured. |
Originators of spam messages are constantly changing their techniques to defeat spam countermeasures; therefore, spam software must be constantly updated to address the changing threat. A manual update procedure is labor intensive and does not scale well in an enterprise environment. This risk may be mitigated by using an automatic... |
|
V-259690
|
Medium |
Exchange must have anti-spam filtering enabled. |
Originators of spam messages are constantly changing their techniques to defeat spam countermeasures; therefore, spam software must be constantly updated to address the changing threat. A manual update procedure is labor intensive and does not scale well in an enterprise environment. This risk may be mitigated by using an automatic... |
|
V-259689
|
Medium |
Exchange must have anti-spam filtering installed. |
Originators of spam messages are constantly changing their techniques to defeat spam countermeasures; therefore, spam software must be constantly updated to address the changing threat. A manual update procedure is labor intensive and does not scale well in an enterprise environment. This risk may be mitigated by using an automatic... |
|
V-259688
|
Medium |
Exchange external/internet-bound automated response messages must be disabled. |
Spam originators, in an effort to refine mailing lists, sometimes monitor transmissions for automated bounce-back messages. Automated messages include such items as "Out of Office" responses, nondelivery messages, and automated message forwarding.
Automated bounce-back messages can be used by a third party to determine if users exist on the server.... |
|
V-259687
|
Medium |
Exchange internal receive connectors must not allow anonymous connections. |
This control is used to limit the servers that may use this server as a relay. If a Simple Mail Transport Protocol (SMTP) sender does not have a direct connection to the internet (for example, an application that produces reports to be emailed), it will need to use an SMTP... |
|
V-259673
|
Medium |
Exchange email-forwarding SMTP domains must be restricted. |
Auto-forwarded email accounts do not meet the requirement for digital signature and encryption of Controlled Unclassified Information (CUI) and Personally Identifiable Information (PII) in accordance with DODI 8520.2 (reference ee) and DOD Director for Administration and Management memorandum, "Safeguarding Against and Responding to the Breach of Personally Identifiable Information".
Use... |
|
V-259672
|
Medium |
Exchange email forwarding must be restricted. |
Auto-forwarded email accounts do not meet the requirement for digital signature and encryption of Controlled Unclassified Information (CUI) and Personally Identifiable Information (PII) in accordance with DODI 8520.2 (reference ee) and DOD Director for Administration and Management memorandum, "Safeguarding Against and Responding to the Breach of Personally Identifiable Information".
Use... |
|
V-259671
|
Medium |
Exchange mailboxes must be retained until backups are complete. |
Backup and recovery procedures are an important part of overall system availability and integrity. Complete backups reduce the chance of accidental deletion of important information and make it possible to have complete recoveries.
It is not uncommon for users to receive and delete messages in the scope of a single... |
|
V-259670
|
Medium |
Exchange internet-facing send connectors must specify a smart host. |
When identifying a "Smart Host" for the email environment, a logical Send connector is the preferred method.
A Smart Host acts as an internet-facing concentrator for other email servers. Appropriate hardening can be applied to the Smart Host, rather than at multiple locations throughout the enterprise.
Failure to identify a... |
|
V-259669
|
Medium |
Exchange Mailbox databases must reside on a dedicated partition. |
In the same way that added security layers can provide a cumulative positive effect on security posture, multiple applications can provide a cumulative negative effect. A vulnerability and subsequent exploit to one application can lead to an exploit of other applications sharing the same security context. For example, an exploit... |
|
V-259668
|
Medium |
The Exchange Post Office Protocol 3 (POP3) service must be disabled. |
POP3 is not approved for use within the DOD. It uses a clear-text-based user name and password and does not support the DOD standard for PKI for email access. User name and password could easily be captured from the network, allowing a malicious user to access other system features. Uninstalling... |
|
V-259667
|
Medium |
The Exchange Internet Message Access Protocol 4 (IMAP4) service must be disabled. |
IMAP4 is not approved for use within the DOD. It uses a clear-text-based user name and password and does not support the DOD standard for PKI for email access. User name and password could easily be captured from the network, allowing a malicious user to access other system features. Uninstalling... |
|
V-259666
|
Medium |
Exchange must not send customer experience reports to Microsoft. |
It is detrimental for applications to provide, or install by default, functionality exceeding requirements or mission objectives. These unnecessary capabilities or services are often overlooked and therefore may remain unsecured. They increase the risk to the platform by providing additional attack vectors.
Applications are capable of providing a wide variety... |
|
V-259665
|
Medium |
Exchange Send Fatal Errors to Microsoft must be disabled. |
It is detrimental for applications to provide, or install by default, functionality exceeding requirements or mission objectives. These unnecessary capabilities or services are often overlooked and therefore may remain unsecured. They increase the risk to the platform by providing additional attack vectors.
Applications are capable of providing a wide variety... |
|
V-259664
|
Medium |
Exchange local machine policy must require signed scripts. |
Scripts often provide a way for attackers to infiltrate a system, especially scripts downloaded from untrusted locations. By setting machine policy to prevent unauthorized script executions, unanticipated system impacts can be avoided. Failure to allow only signed remote scripts reduces the attack vector vulnerabilities from unsigned remote scripts. |
|
V-259663
|
Medium |
Exchange audit data must be on separate partitions. |
Log files help establish a history of activities and can be useful in detecting attack attempts or determining tuning adjustments to improve availability. Audit log content must always be considered sensitive and in need of protection.
Successful exploit of an application server vulnerability may well be logged by monitoring or... |
|
V-259662
|
Medium |
Exchange must protect audit data against unauthorized deletion. |
Log files help establish a history of activities and can be useful in detecting attack attempts or determining tuning adjustments to improve availability. Audit log content must always be considered sensitive and in need of protection. Audit data available for modification by a malicious user can be altered to conceal... |
|
V-259661
|
Medium |
Exchange must protect audit data against unauthorized access. |
Log files help establish a history of activities and can be useful in detecting attack attempts or determining tuning adjustments to improve availability. Audit log content must always be considered sensitive and in need of protection. Audit data available for modification by a malicious user can be altered to conceal... |
|
V-259660
|
Medium |
Exchange must protect audit data against unauthorized read access. |
Log files help establish a history of activities and can be useful in detecting attack attempts or determining tuning adjustments to improve availability. Audit log content must always be considered sensitive and in need of protection. Audit data available for modification by a malicious user can be altered to conceal... |
|
V-259659
|
Medium |
Exchange queue monitoring must be configured with threshold and action. |
Monitors are automated "process watchers" that respond to performance changes and can be useful in detecting outages and alerting administrators where attention is needed. Exchange has built-in monitors that enable the administrator to generate alerts if thresholds are reached, better enabling them to react in a timely fashion.
This field... |
|
V-259657
|
Medium |
Exchange message tracking logging must be enabled. |
A message tracking log provides a detailed log of all message activity as messages are transferred to and from a computer running Exchange.
If events are not recorded, it may be difficult or impossible to determine the root cause of system problems or the unauthorized activities of malicious users. |
|
V-259656
|
Medium |
Exchange email subject line logging must be disabled. |
Log files help establish a history of activities and can be useful in detecting attack attempts or determining tuning adjustments to improve availability. When "message tracking" is enabled, only the sender, recipients, time, and other delivery information is included by default. Information such as the subject and message body is... |
|
V-259655
|
Medium |
The RBAC role for audit log management must be defined and restricted. |
The RBAC role for the audit log management "Audit Log Role" should be defined in the Organizational or Enterprise Domain Security Plan (EDSP) to define the necessary personnel that are required to handle audit logs for the Microsoft Exchange application.
Group membership should be audited regularly by checking the EDSP... |
|
V-259653
|
Medium |
The Exchange email diagnostic log level must be set to the lowest level. |
Log files help establish a history of activities and can be useful in detecting attack attempts or determining tuning adjustments to improve availability. Diagnostic logging, however, characteristically produces large volumes of data and requires care in managing the logs to prevent risk of disk capacity denial-of-service conditions.
Exchange diagnostic logging... |
|
V-259652
|
Medium |
Exchange connectivity logging must be enabled. |
A connectivity log is a record of the SMTP connection activity of the outbound message delivery queues to the destination Mailbox server, smart host, or domain. Connectivity logging is available on Mailbox servers in Exchange 2019 as it holds Mailbox, Client Access, and Hub Transport roles. This must also be... |
|
V-259651
|
Medium |
Exchange auto-forwarding email to remote domains must be disabled or restricted. |
Attackers can use automated messages to determine whether a user account is active, in the office, traveling, and so on. An attacker might use this information to conduct future attacks. Verify Automatic Forwards to remote domains are disabled, except for enterprise mail that must be restricted to forward only to... |
|
V-259650
|
Medium |
Exchange must have authenticated access set to integrated Windows authentication only. |
To mitigate the risk of unauthorized access to sensitive information by entities that have been issued certificates by DOD-approved PKIs, all DOD systems (e.g., networks, web servers, and web portals) must be properly configured to incorporate access control methods that do not rely solely on the possession of a certificate... |
|
V-259649
|
Medium |
Exchange servers must use approved DOD certificates. |
Server certificates are required for many security features in Exchange; without them, the server cannot engage in many forms of secure communication.
Failure to implement valid certificates makes it virtually impossible to secure Exchange's communications. |
|
V-259648
|
Medium |
Exchange must have administrator audit logging enabled. |
Unauthorized or malicious data changes can compromise the integrity and usefulness of the data. Automated attacks or malicious users with elevated privileges have the ability to effect change using the same mechanisms as email administrators. Auditing any changes to access mechanisms not only supports accountability and nonrepudiation for those authorized... |
|
V-259647
|
Medium |
Exchange must have forms-based authentication enabled. |
Identification and Authentication provide the foundation for access control. Access to email services applications in the DOD requires authentication using DOD Public Key Infrastructure (PKI) certificates. Authentication for Outlook Web App (OWA) is used to enable web access to user email mailboxes and should assume that certificate-based authentication has been... |
|
V-259646
|
Medium |
Exchange must use encryption for Outlook Web App (OWA) access. |
This setting controls whether client machines should be forced to use secure channels to communicate with this virtual directory. If this feature is enabled, clients will only be able to communicate with the directory if they are capable of supporting secure communication with the server.
The use of secure communication... |
|
V-259645
|
Medium |
Exchange must use encryption for RPC client access. |
This setting controls whether client machines are forced to use secure channels to communicate with the server. If this feature is enabled, clients will only be able to communicate with the server over secure communication channels.
Failure to require secure connections to the client access server increases the potential for... |
|
V-259697
|
Low |
The Exchange receive connector timeout must be limited. |
Email system availability depends in part on best practice strategies for setting tuning. This configuration controls the number of idle minutes before the connection is dropped. It works in conjunction with the Maximum Inbound Connections Count setting.
Connections, once established, may incur delays in message transfer. If the timeout period... |
|
V-259693
|
Low |
The Exchange Global Recipient Count Limit must be set. |
Email system availability depends in part on best practice strategies for setting tuning configurations. The Global Recipient Count Limit field is used to control the maximum number of recipients that can be specified in a single message sent from this server. Its primary purpose is to minimize the chance of... |
|
V-259685
|
Low |
The Exchange Outbound Connection Timeout must be 10 minutes or less. |
Email system availability depends in part on best practice strategies for setting tuning configurations. This configuration controls the number of idle minutes before the connection is dropped. It works in conjunction with the Maximum Outbound Connections Count setting.
Once established, connections may incur delays in message transfer. The default of... |
|
V-259684
|
Low |
The Exchange Outbound Connection Limit per Domain Count must be controlled. |
Email system availability depends in part on best practice strategies for setting tuning configurations. This configuration controls the maximum number of simultaneous outbound connections from a domain as a delivery tuning mechanism. If the limit is too low, connections may be dropped. If the limit is too high, some domains... |
|
V-259683
|
Low |
The Exchange global outbound message size must be controlled. |
Email system availability depends in part on best practice strategies for setting tuning configurations. Message size limits should be set to 10 MB at most but often are smaller, depending on the organization. The key point in message size is that it should be set globally and should not be... |
|
V-259682
|
Low |
The Exchange global inbound message size must be controlled. |
Email system availability depends in part on best practice strategies for setting tuning configurations. Message size limits should be set to 10 MB at most but often are smaller, depending on the organization. The key point in message size is that it should be set globally and should not be... |
|
V-259681
|
Low |
Exchange message size restrictions must be controlled on send connectors. |
Email system availability depends in part on best practice strategies for setting tuning configurations. For message size restrictions, multiple places exist to set or override inbound or outbound message size. Failure to control the configuration strategy can result in loss of data or system availability.
This setting enables the administrator... |
|
V-259680
|
Low |
Exchange receive connectors must control the number of recipients per message. |
Email system availability depends in part on best practice strategies for setting tuning configurations.
This configuration controls the maximum number of recipients who will receive a copy of a message at one time. This tunable value is related to throughput capacity and can enable the ability to optimize message delivery.... |
|
V-259679
|
Low |
The Exchange send connector connections count must be limited. |
The Exchange Send connector setting controls the maximum number of simultaneous outbound connections allowed for a given SMTP connector and can be used to throttle the SMTP service if resource constraints warrant it. If the limit is too low, connections may be dropped. If the limit is too high, some... |
|
V-259678
|
Low |
The Exchange Receive Connector Maximum Hop Count must be 60. |
Email system availability depends in part on best practice strategies for setting tuning configurations. This setting controls the maximum number of hops (email servers traversed) a message may take as it travels to its destination. Part of the original internet protocol implementation, the hop count limit prevents a message being... |
|
V-259677
|
Low |
Exchange Message size restrictions must be controlled on Receive connectors. |
Email system availability depends in part on best practice strategies for setting tuning configurations. For message size restrictions, multiple places exist to set or override inbound or outbound message size. Failure to control the configuration strategy can result in loss of data or system availability.
This setting enables the administrator... |
|
V-259676
|
Low |
Exchange mail quota settings must not restrict sending mail. |
Mail quota settings control the maximum sizes of a user's mailbox and the system's response if these limits are exceeded. Mailbox data that is not monitored against a quota increases the risk of mail loss due to filled disk space, which can also render the system unavailable. Multiple controls supply... |
|
V-259675
|
Low |
Exchange mail quota settings must not restrict receiving mail. |
Mail quota settings control the maximum sizes of a user's mailbox and the system's response if these limits are exceeded. Mailbox data that is not monitored against a quota increases the risk of mail loss due to filled disk space, which can also render the system unavailable.
Failure to allow... |
|
V-259674
|
Low |
Exchange mailbox stores must mount at startup. |
Administrator responsibilities include the ability to react to unplanned maintenance tasks or emergency situations that may require Mailbox data manipulation. Occasionally, there may be a need to start the server with "unmounted" data stores if manual maintenance is being performed on them. Failure to uncheck the "do not mount on... |
|
V-259658
|
Low |
Exchange circular logging must be disabled. |
Logging provides a history of events performed and can also provide evidence of tampering or attack. Failure to create and preserve logs adds to the risk that suspicious events may go unnoticed and raises the potential that insufficient history will be available to investigate them.
This setting controls how log... |
|
V-259654
|
Low |
Exchange audit record parameters must be set. |
Log files help establish a history of activities and can be useful in detecting attack attempts. This item declares the fields that must be available in the audit log file to adequately research events that are logged.
Audit records should include the following fields to supply useful event accounting: Object... |
