QuRouter toctou vulnerability fixed in 2.6.4.001 QNAP
CVE-2025-68404 Published on October 15, 2026
vcs_pentest Race Condition Authentication Bypass Vulnerability in QuRouter management interface
A time-of-check time-of-use (toctou) race condition vulnerability has been reported to affect QuRouter. If exploited, the vulnerability could allow remote attackers to compromise the security of the system.
We have already fixed the vulnerability in the following version:
QuRouter 2.6.4.001 and later
Vulnerability Analysis
Weakness Type
What is a TOCTTOU Vulnerability?
The software checks the state of a resource before using that resource, but the resource's state can change between the check and the use in a way that invalidates the results of the check. This can cause the software to perform invalid actions when the resource is in an unexpected state. This weakness can be security-relevant when an attacker can influence the state of the resource between check and use. This can happen with shared resources such as files, memory, or even variables in multithreaded programs.
CVE-2025-68404 has been classified to as a TOCTTOU vulnerability or weakness.
Affected Versions
QNAP Systems Inc. QuRouter:- Version 2.6.x and below 2.6.4.001 is affected.