Buffer Overflow Vulnerability in Tenda AC9 Router
CVE-2025-5839

8.7HIGH

Key Information:

Vendor

Tenda
Status
Ac9
Vendor
CVE Published:
7 June 2025

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2025-5839?

A vulnerability in Tenda AC9 routers has been identified, which can be exploited remotely through a buffer overflow in the POST Request Handler. Specifically, the function fromadvsetlanip within the /goform/AdvSetLanip file is impacted. A malicious attacker could manipulate the 'lanMask' argument, leading to potential system compromise. Given that this exploit has been disclosed publicly, organizations using this router version should promptly assess their security measures and apply necessary mitigations.

Affected Version(s)

AC9 15.03.02.13

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-2025-5839 - Proof of Concept

References

https://vuldb.com/?id.311582
vdb-entrytechnical-description
https://vuldb.com/?ctiid.311582
signaturepermissions-required
https://vuldb.com/?submit.591369
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

ysnysn0121 (VulDB User)
.