CVE-2025-5991
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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.
Available Exploits
Related News
There is a "Use After Free" vulnerability in Qt's QHttp2ProtocolHandler in the QtNetwork module. This has been assigned the CVE id CVE-2025-5991.
Affected Products
EU Vulnerability Database
Monitored by ENISA for EU cybersecurity
ENISA Analysis
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.
Affected Products (ENISA)
ENISA Scoring
CVSS Score (4.0)
EPSS Score
ENISA References
Data provided by ENISA EU Vulnerability Database. Last updated: June 11, 2025
GitHub Security Advisories
Community-driven vulnerability intelligence from GitHub
Advisory Details
CVSS Scoring
CVSS Score
CVSS Vector
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
References
Advisory provided by GitHub Security Advisory Database. Published: June 11, 2025, Modified: June 11, 2025