Cybersecurity Triage

List SSH Allow and Deny Rules

You need to find SSH allow-list and deny-list directives across the main config and include files.

Command

grep -RhnE '^(AllowUsers|AllowGroups|DenyUsers|DenyGroups|Match )' etc/ssh

What changed

Nothing changes. The command searches fixture-local SSH config files and prints matching access directives with file and line numbers.

Danger

safe

When to use it

Use during access reviews, server handoffs, or when a user can authenticate but still cannot open an SSH session.

When not to use it

Do not remove allow or deny rules from this output alone; confirm group membership, Match context, and operational ownership first.

Undo or recovery

No undo needed because this command is read-only.

Expected output

Line-numbered SSH access directives from sshd_config and included files.

demo script

Disposable terminal steps

find etc/ssh -type f -print | sort
grep -RhnE '^(AllowUsers|AllowGroups|DenyUsers|DenyGroups|Match )' etc/ssh

Terminal transcript Demo JSON

simulated output

What it looks like

disposable vessel

::fixture-ready::
$ find etc/ssh -type f -print | sort
etc/ssh/sshd_config
etc/ssh/sshd_config.d/access.conf
::exit-code::0
$ grep -RhnE '^(AllowUsers|AllowGroups|DenyUsers|DenyGroups|Match )' etc/ssh
1:DenyUsers test oldadmin
2:AllowGroups ssh-login deployers
6:AllowUsers alice deploy
8:Match Address 198.51.100.0/24
::exit-code::0

YouTube Short

List SSH access rules.

Search sshd config and includes for allow and deny directives before changing access.

experiments

A/B tests to run

Metric: completion_rate

A: Find allow and deny rules.

B: SSH includes can carry access policy.