Hi,

The following vulnerability was published for qtbase-opensource-src.

CVE-2026-78253[0]:
| Uncontrolled recursion in QXmlStreamReader::readElementText() in Qt
| Group Qt allows attackers to cause a denial of service (application
| crash via stack exhaustion) via a crafted XML document.

This for fixed for qt6-base in 6.11.2+dfsg-5, but appears to also
affect Qt5:

https://codereview.qt-project.org/c/qt/qtbase/+/754345
https://github.com/qt/qtbase/commit/f91c48650443262db9be37d5239ebe0db18e9555 (v6.11.2)


If you fix the vulnerability please also make sure to include the
CVE (Common Vulnerabilities & Exposures) id in your changelog entry.

For further information see:

[0] https://security-tracker.debian.org/tracker/CVE-2026-78253
https://www.cve.org/CVERecord?id=CVE-2026-78253

Please adjust the affected versions in the BTS as needed.

Hello,

Bug #1150200 in qtbase-opensource-src reported by you has been fixed in the
Git repository and is awaiting an upload. You can see the commit
message below and you can check the diff of the fix at:

https://salsa.debian.org/qt-kde-team/qt/qtbase/-/commit/9fb2c7e5600222dd087c95d7c347c3b4555483e6
------------------------------------------------------------------------
Backport upstream patch to avoid stack exhaustion in QXmlStreamReader.

Closes: #1150200.
------------------------------------------------------------------------

(this message was generated automatically)
-- 
Greetings

https://bugs.debian.org/1150200

We believe that the bug you reported is fixed in the latest version of
qtbase-opensource-src, which is due to be installed in the Debian FTP archive.

A summary of the changes between this version and the previous one is
attached.

Thank you for reporting the bug, which will now be closed.  If you
have further comments please address them to 1150200@bugs.debian.org,
and the maintainer will reopen the bug report if appropriate.

Debian distribution maintenance software
pp.
Dmitry Shachnev <mitya57@debian.org> (supplier of updated qtbase-opensource-src package)

(This message was generated automatically at their request; if you
believe that there is a problem with it please contact the archive
administrators by mailing ftpmaster@ftp-master.debian.org)
Format: 1.8
Date: Sat, 24 Oct 2026 21:46:16 +0300
Source: qtbase-opensource-src
Architecture: source
Version: 5.15.19+dfsg-6
Distribution: unstable
Urgency: medium
Maintainer: Debian Qt/KDE Maintainers <debian-qt-kde@lists.debian.org>
Changed-By: Dmitry Shachnev <mitya57@debian.org>
Closes: 1150200
Changes:
 qtbase-opensource-src (5.15.19+dfsg-6) unstable; urgency=medium
 .
   * Backport upstream patch to avoid stack exhaustion in QXmlStreamReader
     (CVE-2026-78253, closes: #1150200).
   * Update symbols files from the logs of buildds.
Checksums-Sha1:
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Checksums-Sha256:
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 c103171702456b33da3e637c9c8dc24a2d8941d09eff1cf93a135d9a3c96ca92 235672 qtbase-opensource-src_5.15.19+dfsg-6.debian.tar.xz
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Files:
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