Vulnerability 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 needs to 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

Verify the Ubuntu operating system has all system log files under the "/var/log" directory with a permission set to 640 or less permissive by using the following command:

$ sudo find /var/log -perm /137 -type f -exec stat -c "%n %a" {} \;

If the command displays any output, this is a finding.

Fix

Configure the Ubuntu operating system to set permissions of all log files under the "/var/log" directory to 640 or more restricted by using the following command:

$ sudo find /var/log -perm /137 -type f -exec chmod 640 '{}' \;