CVE-2025-5991

EUVD-2025-18092
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.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
TQtCCNA
2.1 LOW
LOCAL
HIGH
NONE
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
Base Score
CVSS 3.x
EPSS Score
Percentile: 2.08%
Early Detection
Affected products identified ahead of NVD analysis through intelligence sources.
VendorProductVersionSource
qtqt
6.9.0
CNA
Debian logo
Debian Releases
Debian Product
Codename
qt6-base
bookworm
6.4.2+dfsg-10
fixed
forky
6.10.2+dfsg-16
fixed
sid
6.10.2+dfsg-16
fixed
trixie
6.8.2+dfsg-9+deb13u2
fixed
qtbase-opensource-src
bookworm
5.15.8+dfsg-11+deb12u3
fixed
bullseye
5.15.2+dfsg-9+deb11u1
fixed
bullseye (security)
5.15.2+dfsg-9+deb11u2
fixed
forky
5.15.19+dfsg-4
fixed
sid
5.15.19+dfsg-4
fixed
trixie
5.15.15+dfsg-6+deb13u1
fixed
qtbase-opensource-src-gles
bookworm
5.15.8+dfsg-3
fixed
bullseye
5.15.2+dfsg-4
fixed
forky
5.15.19+dfsg-2
fixed
sid
5.15.19+dfsg-2
fixed
trixie
5.15.15+dfsg-2
fixed
Ubuntu logo
Ubuntu Releases
Ubuntu Product
Codename
qt6-base
jammy
needs-triage
noble
needs-triage
oracular
ignored
plucky
ignored
questing
ignored
resolute
needs-triage
qtbase-opensource-src-gles
focal
needs-triage
jammy
needs-triage
noble
needs-triage
oracular
ignored
plucky
ignored
questing
ignored
resolute
needs-triage
xenial
ignored
qtbase-opensource-src
bionic
not-affected
focal
not-affected
jammy
not-affected
noble
not-affected
oracular
ignored
plucky
not-affected
questing
not-affected
resolute
not-affected
xenial
not-affected
Common Weakness Enumeration
References
https://codereview.qt-project.org/c/qt/qtbase/+/643777