Ensure SSH LoginGraceTime is set to one minute or less

MediumLevel 1Automatedlinux

Description

The LoginGraceTime parameter specifies the time allowed for successful authentication to the SSH server. The longer the Grace period is the more open unauthenticated connections can exist. Like other session controls in this session the Grace Period should be limited to appropriate organizational limits to ensure the service is available for needed access.

How it is checked

Audit method: Shell command

shell

alt0() { command -v grep >/dev/null 2>&1 || { echo "step1: grep not installed"; return 1; }; command -v sshd >/dev/null 2>&1 || { echo "step1: sshd not installed"; return 1; }; o=$(bash -c 'sshd -T | grep logingracetime' 2>&1); printf '%s\n' "$o" | tr -s ' \t' '  ' | sed 's/^ //;s/ $//' | grep -Fxq -- 'LoginGraceTime 60' || { echo step1: missing 'LoginGraceTime 60'; return 1; }; }; if alt0; then echo compliant; fi

Expected output: compliant

How it is fixed

Fix method: Guidance or infrastructure patch

Edit the /etc/ssh/sshd_config file to set the parameter as follows: LoginGraceTime 60 Restart sshd : systemctl restart sshd

Properties

Operating systems: alinux-2
Tags: cis-convertedlinux
Reference: CIS Aliyun Linux 2 Benchmark v1.0.0 ARCHIVE - 5.2.15

Check this host

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

shell

tmaegis scan --target linux