Malicious Rogue F5 BIG-IP Administrator Account Creation via tmsh (via process_creation)

ATT&CK techniques

Persistence

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

What it detects

This rule detects the F5 tmsh utility creating an authentication user with an administrator role. Initial access brokers exploiting F5 BIG-IP CVE-2023-46747 provisioned a rogue admin account to lock in privileged appliance control. Creation of a new admin-role user on a network appliance is a strong persistence and account-manipulation indicator.

Reporting behind it

Related detections9 linkedT1136.001 — drag to rearrange

Suspicious Hidden Local Account Creation SqlDbAdmin via Process Creation

PowerShell Local Account Creation With Self-Deleting Script

Suspicious Creation of ctxsvc Local Account via net Command

Suspicious Local Administrator Account Addition via net localgroup

Suspicious Local Account Creation of DefaultService via Net User

Malicious Masquerading Local Account WDAGUtilltyAccount Created via net user

Suspicious Domain User Account Created via Net Command

Suspicious Local Account Creation Named DefaultService

ScreenConnect Administrator Provisioning XML Written to Temp Directory (CWE-288)

Malicious Rogue F5 BIG-IP Administrator Account Creation via tmsh (via process_creation)

Pivot detection · T1136.001 · 9 related

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

Full detection rule

Unlock this rule to view and copy it

The detection logic is included with a plan. Everything else — context, mappings and implementation details — stays free on this page.

Sign in for 3 free unlocks

Signing in gives you 3 unlocks to spend on any rule in the library. No card, and they do not expire.

Also included

Unlocked rules convert on this page — to Splunk SPL or Splunk — Raw Index SPL or Microsoft Sentinel KQL or Microsoft Sentinel ASIM ASIM KQL or Microsoft Defender XDR KQL or Elastic Security KQL or Elastic Security Lucene or Elastic Security ES|QL or CrowdStrike Falcon CQL or SentinelOne PowerQuery or Palo Alto Cortex XDR XQL or Carbon Black Cloud Platform Search or Carbon Black EDR Process Search or Google Security Operations UDM Search or IBM QRadar AQL or Sumo Logic Cloud SIEM Rules expression or Rapid7 InsightIDR LEQL or Graylog Search or OpenSearch Lucene or OpenSearch PPL PPL or Grafana Loki LogQL or SQLite SQL or Zircolite SQLite — with the log-source profile the engine picked, the field map it used, and everything it could not express. Converting a rule you have unlocked costs no further credit.

See it run on a free rule →Convert your own rule →