CVE-2025-6145: Critical Buffer Overflow Vulnerability in TOTOLINK EX1200T

Overview

A severe vulnerability has been discovered in the TOTOLINK EX1200T firmware version 4.1.2cu.5232_B20210713. This vulnerability, designated as CVE-2025-6145, is of critical concern to organizations and individuals leveraging this specific firmware, due to its potential for system compromise and data leakage. The exploit has been made public and can be launched remotely, which further heightens the risk and underscores the urgency to address it.

Vulnerability Summary

CVE ID: CVE-2025-6145
Severity: Critical (8.8 CVSS score)
Attack Vector: Network
Privileges Required: None
User Interaction: None
Impact: Potential system compromise or data leakage

Affected Products

Product | Affected Versions

TOTOLINK EX1200T | 4.1.2cu.5232_B20210713

How the Exploit Works

The vulnerability resides in the /boafrm/formSysLog file, which is a part of the HTTP POST Request Handler component in the TOTOLINK EX1200T firmware. An attacker can manipulate the ‘submit-url’ argument leading to a buffer overflow condition. Buffer overflow can result in unpredictable program behavior, including memory access errors, incorrect results, program termination, or a breach of system security. Since the attack can be launched remotely, it poses a significant risk.

Conceptual Example Code

Here’s a conceptual example of how this vulnerability might be exploited. An attacker might send a malicious HTTP POST request that overruns the buffer, causing a buffer overflow:

POST /boafrm/formSysLog HTTP/1.1
Host: target.example.com
Content-Type: application/x-www-form-urlencoded
submit-url=<malicious_payload>

In this example, `` is a crafted string that’s longer than the buffer size allocated for the ‘submit-url’ argument. This causes the buffer overflow, potentially enabling the attacker to execute arbitrary code or cause a denial of service.

Mitigation and Remediation

Users of the affected TOTOLINK EX1200T firmware are advised to immediately apply vendor patches as soon as they become available. Until patches can be applied, using a Web Application Firewall (WAF) or Intrusion Detection System (IDS) can serve as temporary mitigation, providing some level of protection by detecting or blocking malicious HTTP POST requests designed to exploit this vulnerability. Regular system and security audits, as well as continued vigilance in monitoring system logs, are also recommended to detect any unusual activity.