AIX SSH daemon must be configured to only use Message Authentication Codes (MACs) employing FIPS 140-2 approved cryptographic hash algorithms.
Severity | Group ID | Group Title | Version | Rule ID | Date | STIG Version |
|---|---|---|---|---|---|---|
| medium | V-215294 | SRG-OS-000480-GPOS-00227 | AIX7-00-002111 | SV-215294r991589_rule | 2026-02-06 | 3 |
Description
DoD information systems are required to use FIPS 140-2 approved cryptographic hash functions.
ℹ️ Check
Check the SSH daemon configuration for allowed MACs by running the following command:
# grep -i macs /etc/ssh/sshd_config | grep -v '^#'
MACs hmac-sha1,hmac-sha1-96,hmac-sha2-256,hmac-sha2-256-96,hmac-sha2-512,hmac-sha2-512-96
If no lines are returned, or the returned MAC list contains any MAC that is not FIPS 140-2 approved, this is a finding.
✔️ Fix
Edit the "/etc/ssh/sshd_config" file and add/edit the following line to contain FIPS 140-2 approved ciphers:
MACs hmac-sha1,hmac-sha1-96,hmac-sha2-256,hmac-sha2-256-96,hmac-sha2-512,hmac-sha2-512-96
Restart SSH daemon:
# stopsrc -s sshd
# startsrc -s sshd
Note: If the "MACs" configuration contains any ciphers that are not FIPS 140-2 approved, they should be removed from the configuration file.