WRT54GL · CVE-2026-121930 · Infrastructure
NO FIX YET · SEE WHAT TO DO
Linksys WRT54GL 4.30.18 passes the ping_ip parameter of apply.cgi (Ping Diagnostic) to a system shell without sanitising it, so an authenticated user of the web admin can run OS commands on the router. A public proof of concept exists (linked from VulDB; not retrieved). The model is end of life and the vendor did not respond.
first public Nov 4, 2026 · 2 sources
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Anyone still running a Linksys WRT54GL on firmware 4.30.18. The attacker needs a logged-in admin session (high privileges), so routers with default or weak admin passwords, or with the web admin reachable from the internet or untrusted LAN, are the real risk. Other models and routers whose admin is not reachable and has a strong password can skip it.
Not affected if other-models, remote-management-disabled, web-admin-not-exposed
Who cares authenticated, end-of-life, home-router, linksys, wrt54gl
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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.
This page as .md · .json · in your agent: get_signal("CVE-2026-121930") · CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
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