Title

All shell files must have mode 0755 or less permissive. (Cat I impact)

Discussion

Shells with world/group-write permissions give the ability to maliciously modify the shell to obtain unauthorized access.

Check Content

If /etc/shells exists, check the group ownership of each shell referenced. # cat /etc/shells | xargs -n1 ls -lL Otherwise, check any shells found on the system. # find / -name "*sh" | xargs -n1 ls -lL If a shell has a mode more permissive than 0755, this is a finding.

Fix Text

Change the mode of the shell. # chmod 0755 <shell>

Additional Identifiers

Rule ID: SV-227696r603266_rule

Vulnerability ID: V-227696

Group Title: SRG-OS-000480

Expert Comments

CCIs tied to check.

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