CVE-2025-5991
Low
Description
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.
SeverityLow
CVSS2.1
Exploit probability—
ProductQt
PublishedJun 11, 2025
First seenJun 11, 2025
Weakness typeCWE-416Use after free
How to fix
Sources list no fixed version or patch link for this vulnerability.
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| Qt Qt | 6.9.0 | — |
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