TMA-COS-5.3.5
Ensure default user shell timeout is 900 seconds or less
Description
The default TMOUT determines the shell timeout for users. The TMOUT value is measured in seconds. Having no timeout value associated with a shell could allow an unauthorized user access to another user's shell session (e.g. user walks away from their computer and doesn't lock the screen). Setting a timeout value at least reduces the risk of this happening.
How it is checked
Audit method: Manual review
This recommendation cannot be checked automatically. A scan lists it with these instructions when you pass --include-manual.
Run the following commands and verify all TMOUT lines returned are 900 or less and at least one exists in each file. # grep "^TMOUT" /etc/bash/bashrc TMOUT=900 # grep "^TMOUT" /etc/profile TMOUT=900
How it is fixed
Fix method: Guidance or infrastructure patch
Edit the /etc/bash/bashrc and /etc/profile files (and the appropriate files for any other shell supported on your system) and add or edit any umask parameters as follows: TMOUT=900
Properties
- Operating systems
- Any
- Tags
- container-optimized-oscos
- Reference
- CIS Google Container-Optimized OS Benchmark v1.2.0 - 5.3.5 Ensure default user shell timeout is 900 seconds or less