Title

If csh/tcsh shell is used, AIX must display logout messages. (Cat III impact)

Discussion

If a user cannot explicitly end an operating system session, the session may remain open and be exploited by an attacker; this is referred to as a zombie session. Users need to be aware of whether or not the session has been terminated. Information resources to which users gain access via authentication include, for example, local workstations and remote services. Logoff messages can be displayed after authenticated sessions have been terminated. However, for some types of interactive sessions, including, for example, remote login, information systems typically send logoff messages as final messages prior to terminating sessions.

Check Content

Check if users have their "$HOME/.logout" files. If a user does not have their ".logout" file, or the ".logout" file does not display a logout message, this is a finding.

Fix Text

Create the ".logout" file if it does not exist. Add the following two lines to ".logout" to display a logout message and sleep for "5" seconds: echo "You are being disconnected." sleep 5

Additional Identifiers

Rule ID: SV-215311r958640_rule

Vulnerability ID: V-215311

Group Title: SRG-OS-000281-GPOS-00111

Expert Comments

CCIs tied to check.

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