Overview
A significant vulnerability has been detected in the TOTOLINK A3002R v4.0.0-B20230531.1404 that could potentially compromise the integrity of your systems or lead to substantial data leakage. This vulnerability, designated as CVE-2025-45863, affects a substantial number of TOTOLINK A3002R routers in use worldwide. The importance of this vulnerability cannot be overstated. It presents a considerable risk to the confidentiality, integrity, and availability of your data, thereby making it a critical concern for all users of the affected product.
Vulnerability Summary
CVE ID: CVE-2025-45863
Severity: Critical (9.8 CVSS Score)
Attack Vector: Network
Privileges Required: None
User Interaction: None
Impact: System compromise or data leakage
Affected Products
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Product | Affected Versions
TOTOLINK A3002R | v4.0.0-B20230531.1404
How the Exploit Works
The vulnerability originates within the formMapDelDevice interface of the TOTOLINK A3002R router. Specifically, it is a buffer overflow vulnerability which is triggered via the macstr parameter. A buffer overflow occurs when more data is written into a buffer than it can hold, causing the excess data to overflow onto adjacent memory. In this case, an attacker could send specially crafted data to the macstr parameter, causing the buffer to overflow and allowing them to execute arbitrary code or disrupt the normal operation of the system.
Conceptual Example Code
Here is a conceptual example of how an HTTP request exploiting this vulnerability might look:
POST /formMapDelDevice HTTP/1.1
Host: target.example.com
Content-Type: application/x-www-form-urlencoded
macstr=AA:BB:CC:DD:EE:FF%00XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXIn this example, `AA:BB:CC:DD:EE:FF` is a valid MAC address, and `XXXXXXXXX…` is the overflow data which could include malicious code.
In conclusion, it is strongly advised for all users of the affected TOTOLINK A3002R routers to immediately apply the vendor patch or use a Web Application Firewall (WAF) or Intrusion Detection System (IDS) as a temporary mitigation measure.