The AIX SSH daemon must not allow compression.
Severity | Group ID | Group Title | Version | Rule ID | Date | STIG Version |
|---|---|---|---|---|---|---|
| medium | V-215296 | SRG-OS-000480-GPOS-00227 | AIX7-00-002113 | SV-215296r991589_rule | 2026-02-06 | 3 |
Description
If compression is allowed in an SSH connection prior to authentication, vulnerabilities in the compression software could result in compromise of the system from an unauthenticated connection, potentially with root privileges.
ℹ️ Check
Note: If the installed version of OpenSSH is 7.4 or above, this requirement is not applicable.
Check the SSH daemon configuration for the Compression setting by running:
# grep -i Compression /etc/ssh/sshd_config | grep -v '^#'
Compression no
If the setting is not present, or it is not set to "no", this is a finding.
✔️ Fix
Edit the "/etc/ssh/sshd_config" file and add (or modify) the following line:
Compression no
Restart the SSH daemon:
# stopsrc -s sshd
# startsrc -s sshd