CVE-2025-5991lowCWE-416

CVE-2025-5991: low-severity vulnerability in Qt

Use after free in QHttp2ProtocolHandler

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8Vexday Risk Score

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

ssvc Trackcvss 2.1epss 0.1%
There is a "Use After Free" vulnerability in Qt's QHttp2ProtocolHandler in the QtNetwork module. This only affects HTTP/2 handling, HTTP handling is not affected by this at all. This happens due to a race condition between how QHttp2Stream uploads the body of a POST request and the simultaneous handling of HTTP error responses. This issue only affects Qt 6.9.0 and has been fixed for Qt 6.9.1.
CVSS:4.0/AV:L/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:L/SI:L/SA:L
Affected products
Qt · Qt
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