CVE-2026-121930 Linksys WRT54GL Ping Diagnostic apply.cgi system os command injection
- Exploited in the wild
- Not known
- Fix
- None listed
What is CVE-2026-121930?
CVE-2026-121930 is a critical vulnerability in Linksys WRT54GL, published on 4 Nov 2026.
Official description
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.
Which versions are affected by CVE-2026-121930?
How do I fix CVE-2026-121930?
No fix has been published for CVE-2026-121930 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-121930 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-121930 exists.
Sources
Also known as GHSA-mm59-x26v-4g52.