CVE-2026-121617
HighCVSS 7.5Summary
Linksys E5600 1.1.0.26 has an out-of-bounds write in the init_multipart function of /cgi-bin/upload_fw.cgi (Header Parser). The attack can be launched remotely and the exploit is publicly available. The vendor did not respond and the product is no longer supported.
Risk Assessment
An out-of-bounds write may lead to device crash or remote code execution. Public availability of the exploit increases the attack risk.
Recommendation
Replace the device with a supported model or isolate it from the network, as the vendor will not provide a fix.
Other vulnerabilities in Linksys E5600
See all- CVE-2026-121618Medium
Linksys E5600 1.1.0.26 contains an information disclosure vulnerability in /cgi-bin/fqc.cgi (Factory Quality Control). Remote exploitation is possible and the exploit has been made public. The vendor did not respond and the product is no longer supported.
- CVE-2026-121616Medium
Linksys E5600 1.1.0.26 has an out-of-bounds write in the strcpy function of /cgi-bin/mesh_login.cgi (JSON Request Parser) when manipulating the username/password/token/source/cn/action arguments. The attack can be initiated remotely and the exploit is publicly available. The vendor did not respond and the product is no longer supported.
- CVE-2026-121615Critical
Linksys E5600 1.1.0.26 contains an improper authentication vulnerability in /cgi-bin/mesh_login.cgi (Login Handler). The attack can be launched remotely and the exploit has been publicly disclosed. The vendor did not respond and the product is no longer supported.
- CVE-2025-29229Critical
Linksys E5600 version V1.1.0.26 is vulnerable to command injection in the ddnsStatus function. The description provides no further technical details.
Original NVD description (English source)
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.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS