CVE-2026-121617: high-severity vulnerability in Linksys E5600
Linksys E5600 Header upload_fw.cgi init_multipart out-of-bounds write
Published
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
41Vexday Risk Score
No sign of exploitation. It has a public proof of concept.
ssvc Attendcvss 8.7epss 0.5%
A security flaw has been discovered in Linksys E5600 1.1.0.26. Affected by this issue is the function init_multipart of the file /cgi-bin/upload_fw.cgi of the component Header Parser. The manipulation results in out-of-bounds write. The attack may be launched remotely. The exploit has been released to the public and may 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:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P
Affected products
Linksys · E5600public PoCs found — 1
cve_referencegithub.com/Zimo-666/E5600-cves/tree/main/04-upload-fw-multipart-overflowunverified⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
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