Cisco AAA local account and remote authentication changes

ATT&CK techniques

Persistence → Priv Esc

Recon
Resource Dev
Initial Access
Execution
Persistence
- T1098Account Manipulation
- T1136.001Local Account
Priv Esc
- T1098Account Manipulation
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

Identifies events containing both the keywords 'username' and 'aaa' that indicate local account creation/modification and remote authentication configuration changes on Cisco systems. Attackers may alter local credentials or adjust AAA settings to gain persistence and enable unauthorized access. The rule relies on Cisco AAA telemetry where these keyword strings appear in the logged event details.

Reporting behind it

github.comhttps://github.com/SigmaHQ/sigma/blob/master/rules/network/cisco/aaa/cisco_cli_local_accounts.yml

Related detections9 linkedT1136.001 — drag to rearrange

Suspicious Local Account Creation and Privileged Group Addition via Net.EXE (via process_creation)

Linux: New user created with UID=0 or GID=0/10/27 indicating privileged group access

Suspicious Local Account Creation via Net User in Pre-Ransomware Phase

Suspicious Hidden Local Account Creation via Net User by UAT-8099

Malicious Local Account Creation of Support or Whiteninja via net.exe

Malicious Dynamicweb Unauthenticated Administrator Creation via Setup Default.aspx (via webserver)

Suspicious Hidden Backdoor Account Creation Ending With Dollar Sign (via process_creation)

Malicious Cluster-Admin Role Binding Creation (via audit)

Malicious User Password Change Using Current Hash Password - ChangeNTLM - Mimikatz (via security)

Cisco AAA local account and remote authentication changes

Pivot detection · T1136.001 · 9 related

Changelog

v2

v2
Candidate ingested via manual entry.2026-07-31
v1
No changelog recorded for this version.2026-07-30

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

cisco-aaa-local-account-creation-modification-and-remote-authentication-configur-6d844f0f

title: Cisco AAA local account and remote authentication changes
id: 0ba8a740-3581-405e-91b7-d36b3b3a3f46
status: test
description: Identifies events containing both the keywords 'username' and 'aaa' that indicate local account creation/modification and remote authentication configuration changes on Cisco systems. Attackers may alter local credentials or adjust AAA settings to gain persistence and enable unauthorized access. The rule relies on Cisco AAA telemetry where these keyword strings appear in the logged event details.
author: Austin Clark, Huntrule Team
date: 2019-08-12
modified: 2023-01-04
tags:
  - attack.privilege-escalation
  - attack.persistence
  - attack.t1136.001
  - attack.t1098
logsource:
  product: cisco
  service: aaa
detection:
  keywords:
    - username
    - aaa
  condition: keywords
falsepositives:
  - When remote authentication is in place, this should not change often
level: high
license: DRL-1.1
related:
  - id: 6d844f0f-1c18-41af-8f19-33e7654edfc3
    type: derived
references:
  - https://github.com/SigmaHQ/sigma/blob/master/rules/network/cisco/aaa/cisco_cli_local_accounts.yml

Convert

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