Cisco NX-OS
TMA-CISCO-NXOS-1.2.2
Configure IP Blocking on Failed Logins
Description
After a configured number of failed logins in a set window, offending IP addresses should be blocked from login for a configured amount of time. This effectively makes brute force attacks much less practical, slowing automated processes from a rate of multiple attempts per second to per minute ranges. CIS marks this Manual; automated as a config-line check. Audited against the output of 'show running-config' (run 'terminal length 0' first; do not use 'show running-config all', which adds default values).
How it is checked
Audit method: Configuration pattern
- Pattern
(?m)^login block-for \d+ attempts \d+ within \d+
How it is fixed
Fix method: Guidance or infrastructure patch
! This configuration consists of: - A "watch" time window (in seconds) - the number of failed attempts to trigger on - the amount of time (in seconds) to block further login attempts from that IP address For NX-OS 7.x: login block-for <block time window> attempts <fail count> within <detect time window> for instance: login block-for 120 attempts 5 within 120 For NX-OS 9.x: system login block-for <block time window> attempts <fail count> within <detect time window> for instance: system login block-for 120 attempts 5 within 120 Any values at all will thwart most brute force or dictionary attacks.
Properties
- Operating systems
- Any
- Tags
- cisco-nxosnetworklogging
- Reference
- CIS Cisco NX-OS Benchmark v1.2.0 - 1.2.2 Configure IP Blocking on Failed Logins
Check this host
Run this on a machine you are allowed to audit. The scan is read-only.
tmaegis scan --target cisco-nxos