Stack-Based Buffer Overflow in Belkin F9K1122 Router
CVE-2026-4566

8.7HIGH

Key Information:

Vendor

Belkin

Status
F9k1122
Vendor
CVE Published:
23 March 2026

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2026-4566?

A vulnerability has been identified in the Belkin F9K1122 router version 1.00.33, specifically within the function formWISP5G located in the /goform/formWISP5G file. This flaw allows an attacker to manipulate the 'webpage' argument, potentially leading to a stack-based buffer overflow. The exploit can be executed remotely, giving attackers the means to execute arbitrary code. Despite early notifications to the vendor regarding this security issue, no response has been provided, highlighting the urgency for users to assess and mitigate risks associated with this vulnerability.

Affected Version(s)

F9K1122 1.00.33

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-2026-4566 - Proof of Concept

References

https://vuldb.com/?id.352403
vdb-entrytechnical-description
https://vuldb.com/?ctiid.352403
signaturepermissions-required
https://vuldb.com/?submit.775132
third-party-advisory

CVSS V4

Score:
8.7
Severity:
HIGH
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

LtzHust (VulDB User)
VulDB
.