Out-of-bounds Write Vulnerability in Linksys E5600 Router
CVE-2026-121616

6.9MEDIUM

Key Information:

Vendor: Linksys
Status: E5600
Vendor: CVE Published:; 4 November 2026

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👾 Exploit Exists🟡 Public PoC

What is CVE-2026-121616?

A vulnerability has been found in Linksys E5600 router version 1.1.0.26, specifically within the strcpy function of the /cgi-bin/mesh_login.cgi file, associated with the JSON Request Parser component. Exploitation of this vulnerability involves manipulation of the input parameters such as username, password, token, source, cn, and action, which leads to an out-of-bounds write condition. This issue can be exploited remotely, and exploits are publicly available. Notably, this vulnerability affects products that are no longer supported by the vendor, which raises substantial security concerns for users.

Affected Version(s)

E5600 1.1.0.26

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2026-121616 - Proof of Concept