CVE-2026-121931
Linksys WRT54GL Traceroute Diagnostic Function apply.cgi system os command injection
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.
Fixes and workarounds
No remediation reported in collected sources.
Missing remediation information is not evidence that no patch exists.
Affected products and versions
| Product | Versions | Authority |
|---|---|---|
| WRT54GL Linksys |
4.30.18 (affected) | CNA: VulDB |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 4.0 / 9.4 critical |
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 | CNA: VulDB |
| 3.1 / 9.1 critical |
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 | CNA: VulDB |
| 3.0 / 9.1 critical |
CVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H/E:P/RL:X/RC:C | CNA: VulDB |
| 2.0 / 8.3 high |
AV:N/AC:L/Au:M/C:C/I:C/A:C/E:POC/RL:ND/RC:C | CNA: VulDB |
Exploit evidence
References
- https://vuldb.com/vuln/431043CNA: VulDB · vdb-entry, technical-description
- https://vuldb.com/vuln/431043/ctiCNA: VulDB · signature, permissions-required
- https://vuldb.com/cve/CVE-2026-121931CNA: VulDB · third-party-advisory
- https://vuldb.com/submit/1024099CNA: VulDB · third-party-advisory
- https://github.com/Zimo-666/WRT54GL-cves/tree/main/CVE-TBD-traceroute-ip-command-injectionCNA: VulDB · exploit
- https://www.linksys.com/CNA: VulDB · product
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