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.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Qt | Qt | 6.7.0 – < 6.8.8, 6.9.0 – < 6.11.1 | 6.8.8 |
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.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | qt6-svg | 6.10.2-6 | — |
| Debian 13 | qt6-svg | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | qt6-svg | No fix yet | — |
| Ubuntu 26.04 LTS | qt6-svg | No fix yet | — |
| Ubuntu 25.10 | qt6-svg | No fix yet | — |
| Ubuntu 24.04 LTS | qt6-svg | No fix yet | — |
| Ubuntu 22.04 LTS | qt6-svg | No fix yet | — |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | qt6-svg | 6.11.0-2.1 | openSUSE-SU-2026:10742-1 |
Advisories 2
- WID-SEC-2026-1387 QT: Schwachstelle ermöglicht Denial of Service BSI CERT-Bund (WID) · May 20, 2026
- openSUSE-SU-2026:10742-1 libQt6Svg6-6.11.0-2.1 on GA media SUSE / openSUSE Security Updates · May 11, 2026