---
id: CVE-2026-121930
title: Linksys WRT54GL Ping Diagnostic apply.cgi system os command injection
summary: >-
  A weakness has been identified in Linksys WRT54GL 4.30.18. The affected
  element is the function system of the file apply.cgi of the component Ping
  Diagnostic. This manipulation of the argument ping_ip causes os command
  injection. The att…
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:R'
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: '2026-11-04T18:30:11.131Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-121930'
references:
  - url: 'https://vuldb.com/vuln/431042'
    label: >-
      VDB-431042 | Linksys WRT54GL Ping Diagnostic apply.cgi system os command
      injection
  - url: 'https://vuldb.com/vuln/431042/cti'
    label: 'VDB-431042 | CTI Indicators (IOB, IOC, TTP, IOA)'
  - url: 'https://vuldb.com/cve/CVE-2026-121930'
    label: CVE-2026-121930 | CVE Analysis and Report
  - url: 'https://vuldb.com/submit/1024098'
    label: 'Submit #1024098 | Linksys WRT54GL 4.30.18 OS Command Injection (CWE-78)'
  - url: >-
      https://github.com/Zimo-666/WRT54GL-cves/tree/main/CVE-TBD-ping-ip-command-injection
  - url: 'https://www.linksys.com/'
tags:
  - cve.org
ingestedAt: '2026-11-05T21:36:00.490Z'
epss: 0.02722
epssPercentile: 0.86129
---

## Overview

A weakness has been identified in Linksys WRT54GL 4.30.18. The affected element is the function system of the file apply.cgi of the component Ping Diagnostic. This manipulation of the argument ping_ip causes os command injection. The attack can be initiated remotely. The exploit has been made available to the public and could be used for attacks. 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.