Buffer overflow in Qt
CVE-2026-6210
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.
Vulnerability class: Buffer Overflow
Published · last modified .
EPSS exploit prediction
EPSS: 0.005 (38.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 38th percentile — 38.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.005 · change: +0.002
Affected products
- Qt — versions 6.7.0, 6.9.0
- The Qt Company — versions 6.7.0, 6.9.0