A type confusion vulnerability in Qt SVG allows an attacker to cause an application crash via a crafted SVG image.



When processing SVG marker references, the renderer retrieves a node by its id attribute and casts it to QSvgMarker* without verifying the node type. A non-marker element (such as a <line> element) that references itself as a marker triggers an out-of-bounds heap read due to the object size difference between QSvgLine and QSvgMarker,
followed by an endless recursion that bypasses the marker recursion
guard through incorrect virtual dispatch. The result is an application
crash (denial of service).



This issue affects Qt SVG: 
from 6.7.0 before 6.8.8, from 6.9.0 before 6.11.1.

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Fixes

Solution

Apply fix: https://codereview.qt-project.org/c/qt/qtsvg/+/724887


Workaround

No workaround given by the vendor.

History

Sat, 16 May 2026 00:15:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

cvssV3_1

{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H'}

threat_severity

Moderate


Wed, 06 May 2026 19:45:00 +0000

Type Values Removed Values Added
First Time appeared The Qt Company
The Qt Company qt
Vendors & Products The Qt Company
The Qt Company qt

Wed, 06 May 2026 14:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Wed, 06 May 2026 12:15:00 +0000

Type Values Removed Values Added
Description A type confusion vulnerability in Qt SVG allows an attacker to cause an application crash via a crafted SVG image. When processing SVG marker references, the renderer retrieves a node by its id attribute and casts it to QSvgMarker* without verifying the node type. A non-marker element (such as a <line> element) that references itself as a marker triggers an out-of-bounds heap read due to the object size difference between QSvgLine and QSvgMarker, followed by an endless recursion that bypasses the marker recursion guard through incorrect virtual dispatch. The result is an application crash (denial of service). This issue affects Qt SVG:  from 6.7.0 before 6.8.8, from 6.9.0 before 6.11.1.
Title Type confusion and heap-buffer-overflow in Qt SVG marker handling causing application crash
Weaknesses CWE-122
CWE-843
References
Metrics cvssV4_0

{'score': 8.7, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N'}


Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: TQtC

Published:

Updated: 2026-05-06T13:11:44.674Z

Reserved: 2026-04-13T12:16:27.416Z

Link: CVE-2026-6210

cve-icon Vulnrichment

Updated: 2026-05-06T13:11:37.140Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-05-06T12:16:49.957

Modified: 2026-05-07T15:10:53.070

Link: CVE-2026-6210

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-05-06T11:59:01Z

Links: CVE-2026-6210 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2026-05-06T19:30:10Z

Weaknesses