F5 BIG-IP Proxy: Detect POST requests exploiting CVE-2023-46747 via /mgmt/tm/util/bash

Alerts on POST requests containing /mgmt/tm/util/bash plus TMUI control/user-create form parameters indicative of CVE-2023-46747 exploitation.

FreeReviewedSigma · High · v5

Category: proxy
Author: Nasreddine Bencherchali (Nextron Systems) (SigmaHQ), DRL 1.1
Published: 2023-11-08
Updated: 2026-07-31

Analysis Detection

ATT&CK techniques

Initial Access

Recon
Resource Dev
Initial Access
- T1190Exploit Public-Facing Application
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule identifies likely exploitation attempts for CVE-2023-46747 by matching specific HTTP POST traffic on F5 BIG-IP proxy endpoints. It looks for requests containing a bash utility path and exact form-related parameters that are used to reach a user creation workflow. The detection relies on proxy HTTP telemetry fields including the HTTP method and request URI, plus the presence of the expected body content patterns in the POST body.

Reporting behind it

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F5 BIG-IP Proxy: Detect POST requests exploiting CVE-2023-46747 via /mgmt/tm/util/bash

Pivot detection · T1190 · 9 related

Changelog

v5
Candidate ingested via manual entry.2026-07-31
v4
Candidate ingested via manual entry.2026-07-31
v3
Candidate ingested via manual entry.2026-07-31
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.

f5-big-ip-proxy-exploitation-attempt-targeting-mgmt-tm-util-bash-cve-2023-46747-f195b2ff

title: "F5 BIG-IP Proxy: Detect POST requests exploiting CVE-2023-46747 via /mgmt/tm/util/bash"
id: 442e1bb2-92f8-4343-bd4d-356cc372c9ed
related:
  - id: e9928831-ba14-42ea-a4bc-33d352b9929a
    type: similar
  - id: f195b2ff-e542-41bf-8d91-864fb81e5c20
    type: derived
status: test
description: This rule identifies likely exploitation attempts for CVE-2023-46747 by matching specific HTTP POST traffic on F5 BIG-IP proxy endpoints. It looks for requests containing a bash utility path and exact form-related parameters that are used to reach a user creation workflow. The detection relies on proxy HTTP telemetry fields including the HTTP method and request URI, plus the presence of the expected body content patterns in the POST body.
references:
  - https://github.com/AliBrTab/CVE-2023-46747-POC/tree/main
  - https://github.com/0xorOne/nuclei-templates/blob/2fef4270ec6e5573d0a1732cb18bcfc4b1580a88/http/cves/2023/CVE-2023-46747.yaml
  - https://mp.weixin.qq.com/s/wUoBy7ZiqJL2CUOMC-8Wdg
  - https://www.praetorian.com/blog/refresh-compromising-f5-big-ip-with-request-smuggling-cve-2023-46747/
  - https://github.com/SigmaHQ/sigma/blob/master/rules-emerging-threats/2023/Exploits/CVE-2023-46747/proxy_cve_2023_46747_f5_remote_code_execution.yml
author: Nasreddine Bencherchali (Nextron Systems), Huntrule Team
date: 2023-11-08
tags:
  - attack.initial-access
  - attack.t1190
  - cve.2023-46747
  - detection.emerging-threats
logsource:
  category: proxy
  definition: "Requirements: The POST request body data must be collected in order to make use of this detection"
detection:
  selection:
    cs-method: POST
    c-uri|contains: /mgmt/tm/util/bash
  keywords_hex:
    "|all":
      - 2f746d75692f436f6e74726f6c2f666f726d
      - 666f726d5f706167653d253266746d756925326673797374656d253266757365722532666372656174652e6a7370
  keywords_plain:
    "|all":
      - /tmui/Control/form
      - form_page=%2ftmui%2fsystem%2fuser%2fcreate.jsp
  condition: selection and (keywords_hex or keywords_plain)
falsepositives:
  - Unlikely
level: high
license: DRL-1.1

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