CVE-2025-6338criticalCWE-459

CVE-2025-6338: critical vulnerability in Qt

Possible denial of service with multiple incoming connections to a Schannel based server with a TLS backend

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28Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 9.2epss 0.4%
There is an incomplete cleanup vulnerability in Qt Network's Schannel support on Windows which can lead to a Denial of Service over a long period. This issue affects Qt from 5.15.0 through 6.8.3, from 6.9.0 before 6.9.2.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H
Affected products
Qt · Qt
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