Ensure sshd LogLevel is configured

MediumLevel 1Automatedaix

Description

SSH provides several logging levels with varying amounts of verbosity. The DEBUG options are specifically not recommended other than strictly for debugging SSH communications. These levels provide so much data that it is difficult to identify important security information, and may violate the privacy of users. Audit: evaluates the effective configuration from `sshd -T` (Match blocks must be reviewed separately).

How it is checked

Audit method: Shell command

shell

command -v sshd >/dev/null 2>&1 || exit 1; out=$(sshd -T 2>/dev/null) || exit 1; r=compliant; for p in '^loglevel[[:blank:]]+(VERBOSE|INFO)$'; do printf '%s\n' "$out" | grep -Eiq -- "$p" || r="not matched: $p"; done; echo "$r"

Expected output: compliant

How it is fixed

Fix method: Guidance or infrastructure patch

Edit the /etc/ssh/sshd_config file to set the parameter above any Match set entries as follows: LogLevel VERBOSE - OR - LogLevel INFO Re-cycle the sshd daemon to pick up the configuration changes: stopsrc -s sshd startsrc -s sshd Note: First occurrence of a option takes precedence, Match set statements withstanding.

Properties

Operating systems: Any
Tags: aixssh
Reference: CIS IBM AIX 7 Benchmark v1.2.0 - 4.6.3.10 Ensure sshd LogLevel is configured

Check this host

Run this on a machine you are allowed to audit. The scan is read-only.

shell

tmaegis scan --target aix