Buffer Overflow in Tenda AC21 Router
CVE-2025-11091

8.7HIGH

Key Information:

Vendor

Tenda
Status
Ac21
Vendor
CVE Published:
28 September 2025

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2025-11091?

A buffer overflow vulnerability has been identified in Tenda AC21 routers in versions up to 16.03.08.16. This flaw resides in the sscanf function of the /goform/SetStaticRouteCfg file, allowing an attacker to manipulate the argument list. Such manipulation can lead to a potential remote attack, as the exploit is publicly available. It is crucial for users to be aware of this vulnerability and apply necessary security measures to safeguard their devices.

Affected Version(s)

AC21 16.03.08.0

AC21 16.03.08.1

AC21 16.03.08.2

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-2025-11091 - Proof of Concept

References

https://vuldb.com/?id.326173
vdb-entrytechnical-description
https://vuldb.com/?ctiid.326173
signaturepermissions-required
https://vuldb.com/?submit.661806
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

MaximDeVere (VulDB User)
JSON
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CVE-2025-11091 : Buffer Overflow in Tenda AC21 Router