CVE-2026-121617
Linksys E5600 Header upload_fw.cgi init_multipart out-of-bounds write
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.
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 |
|---|---|---|
| E5600 Linksys |
1.1.0.26 (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 / 8.7 high |
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 | CNA: VulDB |
| 3.1 / 7.5 high |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:X/RC:C | CNA: VulDB |
| 3.0 / 7.5 high |
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:X/RC:C | CNA: VulDB |
| 2.0 / 7.8 high |
AV:N/AC:L/Au:N/C:N/I:N/A:C/E:POC/RL:ND/RC:C | CNA: VulDB |
Exploit evidence
- https://github.com/Zimo-666/E5600-cves/tree/main/04-upload-fw-multipart-overflow
exploit · CNA: VulDB
References
- https://vuldb.com/vuln/430465CNA: VulDB · vdb-entry, technical-description
- https://vuldb.com/vuln/430465/ctiCNA: VulDB · signature, permissions-required
- https://vuldb.com/cve/CVE-2026-121617CNA: VulDB · third-party-advisory
- https://vuldb.com/submit/1023313CNA: VulDB · third-party-advisory
- https://github.com/Zimo-666/E5600-cves/tree/main/04-upload-fw-multipart-overflowCNA: VulDB · exploit
- https://www.linksys.com/CNA: VulDB · product
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