---
id: CVE-2026-121931
title: >-
  Linksys WRT54GL Traceroute Diagnostic Function apply.cgi system os command
  injection
summary: >-
  A security vulnerability has been detected in Linksys WRT54GL 4.30.18. The
  impacted element is the function system of the file apply.cgi of the component
  Traceroute Diagnostic Function. Such manipulation of the argument
  traceroute_ip lea…
severity: critical
cvss: 9.1
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H/E:P/RL:X/RC:C'
cvssSource: cna
cwe:
  - CWE-78
  - CWE-77
vendor: Linksys
product: WRT54GL
affected:
  - WRT54GL 4.30.18
published: '2026-11-04'
updated: '2026-11-04'
sourceUpdated: '2026-11-04T18:45:14.398Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-121931'
references:
  - url: 'https://vuldb.com/vuln/431043'
    label: >-
      VDB-431043 | Linksys WRT54GL Traceroute Diagnostic Function apply.cgi
      system os command injection
  - url: 'https://vuldb.com/vuln/431043/cti'
    label: 'VDB-431043 | CTI Indicators (IOB, IOC, TTP, IOA)'
  - url: 'https://vuldb.com/cve/CVE-2026-121931'
    label: CVE-2026-121931 | CVE Analysis and Report
  - url: 'https://vuldb.com/submit/1024099'
    label: 'Submit #1024099 | Linksys WRT54GL 4.30.18 OS Command Injection (CWE-78)'
  - url: >-
      https://github.com/Zimo-666/WRT54GL-cves/tree/main/CVE-TBD-traceroute-ip-command-injection
  - url: 'https://www.linksys.com/'
tags:
  - cve.org
ingestedAt: '2026-11-05T21:36:00.497Z'
epss: 0.02722
epssPercentile: 0.86129
---

## Overview

A security vulnerability has been detected in Linksys WRT54GL 4.30.18. The impacted element is the function system of the file apply.cgi of the component Traceroute Diagnostic Function. Such manipulation of the argument traceroute_ip leads to os command injection. The attack can be launched remotely. The exploit has been disclosed publicly and may be used. The vendor was contacted early about this disclosure but did not respond in any way. This vulnerability only affects products that are no longer supported by the maintainer.

## Affected

- `WRT54GL 4.30.18`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.