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OpenAdvisories
Medium · 4.6 CVE-2026-76151 EUVD-2026-80385GHSA-32mm-x94q-6h38

Out-of-bounds read (buffer over-read) vulnerability in HTTP Cache-Control response header parsing impacts Qt Framework (QtNetwork module)

Published Sep 16, 2026 · Updated Sep 16, 2026 · Assigned by Qt

Description

Out-of-bounds read (buffer over-read) in the HTTP Cache-Control response header parsing in the QtNetwork module in Qt Group Qt 6.0.0 through 6.8.8, and 6.9.0 through 6.11.1, allows remote attackers to cause a denial of service (application crash) via an excessively large Cache-Control header value returned by an untrusted or compromised HTTP server to an application using QNetworkAccessManager. Only the client side of the connection is affected and 32-bit builds are not affected; the out-of-bounds access is read-only, with no information disclosure and no code execution.

Affected products

VendorProductAffectedFixed
qt qt 6.0.0 – < 6.8.9, 6.9.0 – < 6.11.2 6.8.9

Fixed in Linux distributions

Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.

ReleasePackageFixed inAdvisory
Debian 14 qt6-base 6.11.2+dfsg-5 —
Debian 13 qt6-base No fix yet —
Debian 12 qt6-base No fix yet —
ReleasePackageFixed inAdvisory
Ubuntu 26.10 qt6-base +1 No fix yet —
Ubuntu 26.04 LTS qt6-base +1 No fix yet —
Ubuntu 24.04 LTS qt6-base No fix yet —
Ubuntu 22.04 LTS qt6-base No fix yet —
Show 5 more (older releases, extended support, other products)
ReleasePackageFixed inAdvisory
Ubuntu Pro 24.04 LTS qtbase-opensource-src No fix yet —
Ubuntu Pro 22.04 LTS qtbase-opensource-src No fix yet —
Ubuntu Pro 20.04 LTS qtbase-opensource-src No fix yet —
Ubuntu Pro 18.04 LTS qtbase-opensource-src No fix yet —
Ubuntu Pro 16.04 LTS qtbase-opensource-src No fix yet —
ReleasePackageFixed inAdvisory
openSUSE Tumbleweed AusweisApp 2.6.0-1.1 openSUSE-SU-2026:12071-1

Amazon Linux

ReleasePackageFixed inAdvisory
Amazon Linux 2 qt5-qtbase +9 5.15.3-1.amzn2.0.4 ALAS2-2026-3980

Advisories 3

References