Stack-Based Buffer Overflow in TOTOLINK A950RG by TOTOLINK
CVE-2026-121600

9.4CRITICAL

Key Information:

Vendor

Totolink
Status
A950rg
Vendor
CVE Published:
4 November 2026

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2026-121600?

A vulnerability has been identified in the TOTOLINK A950RG router, specifically in version 4.1.2cu.5268_B20221104. The flaw resides in the MAC Filter Handler component, within the setMacFilterRules function found in /cgi-bin/cstecgi.cgi. This issue allows attackers to manipulate the argument 'addEffect', leading to a stack-based buffer overflow. Exploitation of this vulnerability can be initiated remotely, potentially compromising the router's security.

Affected Version(s)

A950RG 4.1.2cu.5268_B20221104

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-2026-121600 - Proof of Concept

References

https://vuldb.com/vuln/430442
vdb-entrytechnical-description
https://vuldb.com/vuln/430442/cti
signaturepermissions-required
https://vuldb.com/cve/CVE-2026-121600
third-party-advisory

CVSS V4

Score:
9.4
Severity:
CRITICAL
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • 🟡

    Public PoC available

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

LiuYijun_JX.SGCC (VulDB User)
.