CVE-2026-121930: critical vulnerability in Linksys WRT54GL
Linksys WRT54GL Ping Diagnostic apply.cgi system os command injection
Published
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
48Vexday Risk Score
No sign of exploitation. It has a public proof of concept.
ssvc Attendcvss 9.4epss 2.7%
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.
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
Affected products
Linksys · WRT54GLpublic PoCs found — 1
cve_referencegithub.com/Zimo-666/WRT54GL-cves/tree/main/CVE-TBD-ping-ip-command-injectionunverified⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
Related CVEs — Linksys WRT54GL
In the same product, most dangerous first.
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