Vulnerability in Linksys E5600

[ Why it matters ]Priority signals

• Urgent advisory from BSI

[ Description ]Official description

A vulnerability was identified in Linksys E5600 1.1.0.26. Affected by this vulnerability is the function strcpy of the file /cgi-bin/mesh_login.cgi of the component JSON Request Parser. The manipulation of the argument username/password/token/source/cn/action leads to out-of-bounds write. The attack may be initiated remotely. The exploit is publicly available and might 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 ]Fixes and patches

No fix or interim patch is linked from our sources yet. Check the vendor references below and limit exposure of affected systems until a fix is available.

[ Advisories ]Government CERT advisories

• BSI CERT-Bund3 Nov 2026WID-SEC-2026-4327

  Linksys Router E5600: Multiple vulnerabilities allow privilege escalation Translated from German

  Risk criticalCVE-2026-121616CVE-2026-121615CVE-2026-121618+1 more CVEs

[ References ]References

• github.com/Zimo-666/E5600-cves/tree/main/03-mesh-login-global-overflow
• vuldb.com/cve/CVE-2026-121616
• vuldb.com/submit/1023312
• vuldb.com/vuln/430464
• vuldb.com/vuln/430464/cti
• www.linksys.com