Overview
The cybersecurity landscape experiences constant changes, with new vulnerabilities emerging almost daily. One such vulnerability is CVE-2025-51451, a critical security flaw that affects TOTOLINK EX1200T firmware version 4.1.2cu.5215. This vulnerability allows attackers to bypass login authentication by sending a specific request through formLoginAuth.htm, potentially compromising the system or causing data leakage. As TOTOLINK EX1200T is a widely used firmware, this vulnerability can have far-reaching repercussions, potentially affecting a large number of internet users.
Vulnerability Summary
CVE ID: CVE-2025-51451
Severity: Critical, CVSS Score 9.8
Attack Vector: Network
Privileges Required: None
User Interaction: None
Impact: System compromise and potential data leakage
Affected Products
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Product | Affected Versions
TOTOLINK EX1200T Firmware | 4.1.2cu.5215
How the Exploit Works
The exploit takes advantage of a flaw in the login authentication process in TOTOLINK EX1200T firmware. Specifically, an attacker can send a specifically crafted request to the formLoginAuth.htm page. This request causes the system to bypass the regular login process, granting the attacker unauthorized access to the system. With this access, the attacker can then compromise the system or cause data leakage.
Conceptual Example Code
Here is a conceptual example of how the vulnerability might be exploited. Please note that this is a simplified example and the actual exploit would require more complex coding.
POST /formLoginAuth.htm HTTP/1.1
Host: target.example.com
Content-Type: application/x-www-form-urlencoded
username=attacker&password=none&operation=loginIn this example, the attacker sends a POST request to the formLoginAuth.htm page. The username and password fields are filled in with arbitrary values. The operation parameter is set to “login”, triggering the login process. However, due to the vulnerability in the firmware, this login process is bypassed, and the attacker gains unauthorized access to the system.
Mitigation and Prevention
Users of the affected TOTOLINK EX1200T firmware are advised to apply the vendor patch as soon as it becomes available. Until then, a Web Application Firewall (WAF) or Intrusion Detection System (IDS) can be used as a temporary mitigation measure to detect and block attempts to exploit this vulnerability. Regular updates and monitoring of the system are also recommended to prevent future attacks.