Qt 5.x before 5.15.6 and 6.x through 6.1.2 has an out-of-bounds write in QOutlineMapper::convertPath (called from QRasterPaintEngine::fill and QPaintEngineEx::stroke).
https://www.qt.io/blog/qt-5.15-extended-support-for-subscription-license-holders
https://wiki.qt.io/Qt_5.15_Release#Known_Issues
https://security.gentoo.org/glsa/202402-03
https://github.com/qt/qtbase/commit/6b400e3147dcfd8cc3a393ace1bd118c93762e0c
https://github.com/qt/qtbase/commit/202143ba41f6ac574f1858214ed8bf4a38b73ccd
https://github.com/qt/qtbase/commit/1ca02cf2879a5e1511a2f2109f0925cf4c892862
https://github.com/google/oss-fuzz-vulns/blob/main/vulns/qt/OSV-2021-903.yaml