Title

Ubuntu 24.04 LTS must generate system journal entries without revealing information that could be exploited by adversaries. (Cat II impact)

Discussion

Any operating system providing too much information in error messages risks compromising the data and security of the structure, and content of error messages must be carefully considered by the organization. Organizations carefully consider the structure/content of error messages. The extent to which information systems are able to identify and handle error conditions is guided by organizational policy and operational requirements. Information that could be exploited by adversaries includes, for example, erroneous logon attempts with passwords entered by mistake as the username, mission/business information that can be derived from (if not stated explicitly by) information recorded, and personal information, such as account numbers, social security numbers, and credit card numbers.

Check Content

Verify the /run/log/journal and /var/log/journal directories have permissions set to "2640" or less permissive with the following command: $ sudo find /run/log/journal /var/log/journal -type d -exec stat -c "%n %a" {} \; /run/log/journal 2640 /var/log/journal 2640 /var/log/journal/d5745ad455d34fb8b6f78be37c1fcd3e 2640 If any output returned has a permission set greater than 2640, this is a finding. Verify all files in the /run/log/journal and /var/log/journal directories have permissions set to "640" or less permissive with the following command: $ sudo find /run/log/journal /var/log/journal -type f -exec stat -c "%n %a" {} \; /var/log/journal/d5745ad455d34fb8b6f78be37c1fcd3e/system.journal 640 /var/log/journal/d5745ad455d34fb8b6f78be37c1fcd3e/user-1000@0005f97cd4a8c9b5a.journal~ 640 /var/log/journal/d5745ad455d34fb8b6f78be37c1fcd3e/system@0005f97cd2a1e0a7-d58b848af46813a4.journal~ 640 /var/log/journal/d5745ad455d34fb8b6f78be37c1fcd3e/system@0005f97cb900e501-55ea053b7f75ae1c.journal~ 640 /var/log/journal/d5745ad455d34fb8b6f78be37c1fcd3e/user-1000.journal 640 If any output returned has a permission set greater than "640", this is a finding.

Fix Text

Configure the system to set the appropriate permissions to the files and directories used by the systemd journal: $ sudo nano /usr/lib/tmpfiles.d/systemd.conf Edit the following lines of the configuration file: z /run/log/journal 2640 root systemd-journal - - Z /run/log/journal/%m ~2640 root systemd-journal - - z /var/log/journal 2640 root systemd-journal - - z /var/log/journal/%m 2640 root systemd-journal - - z /var/log/journal/%m/system.journal 0640 root systemd-journal - - Note: The system must be restarted for these settings to take effect.

Additional Identifiers

Rule ID: SV-270757r1066760_rule

Vulnerability ID: V-270757

Group Title: SRG-OS-000205-GPOS-00083

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.