Buffer Overflow Vulnerability in TOTOLINK A3300R Router
CVE-2025-12239

8.7HIGH

Key Information:

Vendor

Totolink
Status
A3300r
Vendor
CVE Published:
27 October 2025

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2025-12239?

A buffer overflow vulnerability has been discovered in the TOTOLINK A3300R router, specifically within the setDdnsCfg function located in /cgi-bin/cstecgi.cgi. This weakness enables attackers to exploit the router from a remote location, potentially compromising the device. This issue affects version 17.0.0cu.557_B20221024 and is significant due to the public availability of the corresponding exploit, raising concerns about the security of connected networks.

Affected Version(s)

A3300R 17.0.0cu.557_B20221024

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-2025-12239 - Proof of Concept

References

https://vuldb.com/?id.329909
vdb-entrytechnical-description
https://vuldb.com/?ctiid.329909
signaturepermissions-required
https://vuldb.com/?submit.673721
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

yhryhryhr_miemie (VulDB User)
JSON
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CVE-2025-12239 : Buffer Overflow Vulnerability in TOTOLINK A3300R Router