Buffer Overflow Vulnerability in TOTOLINK A720R Router
CVE-2025-9303

8.7HIGH

Key Information:

Vendor

Totolink
Status
A720r
Vendor
CVE Published:
21 August 2025

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2025-9303?

A critical security flaw has been identified in the TOTOLINK A720R router, specifically within the setParentalRules function located in /cgi-bin/cstecgi.cgi. This vulnerability is due to improper handling of the 'desc' argument, which can lead to a buffer overflow. Attackers can exploit this vulnerability remotely, potentially compromising the router’s functionality and security. Publicly available exploit code increases the urgency for users to take necessary precautions.

Affected Version(s)

A720R 4.1.5cu.630_B20250509

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-2025-9303 - Proof of Concept

References

https://vuldb.com/?id.320908
vdb-entrytechnical-description
https://vuldb.com/?ctiid.320908
signaturepermissions-required
https://vuldb.com/?submit.632410
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

QMSSDXN (VulDB User)
.
CVE-2025-9303 : Buffer Overflow Vulnerability in TOTOLINK A720R Router