CVE-2021-38593
CVE-2021-38593 is a high-severity vulnerability in Qt with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-787.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- CVSS v2: 5.0
- EPSS exploit prediction: 3% (86th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-787
- Affected product: Qt
- Published:
- Last modified:
Description
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).
Frequently asked questions
- What is CVE-2021-38593?
- 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).
- How severe is CVE-2021-38593?
- CVE-2021-38593 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
- Is CVE-2021-38593 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-38593?
- CVE-2021-38593 primarily affects Qt. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2021-38593?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2021-38593 published?
- CVE-2021-38593 was published on 2021-08-12 and last updated on 2026-06-17.
References
- https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=35566
- https://github.com/google/oss-fuzz-vulns/blob/main/vulns/qt/OSV-2021-903.yaml
- https://github.com/qt/qtbase/commit/1ca02cf2879a5e1511a2f2109f0925cf4c892862
- https://github.com/qt/qtbase/commit/202143ba41f6ac574f1858214ed8bf4a38b73ccd
- https://github.com/qt/qtbase/commit/6b400e3147dcfd8cc3a393ace1bd118c93762e0c
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/36VN2WKMNQUSTF6ZW2X52NPAJVXJ4S5I/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HY5YCSDCTLHVMP3OXOM6HNTWHV6DBHDX/
- https://security.gentoo.org/glsa/202402-03
- https://wiki.qt.io/Qt_5.15_Release#Known_Issues
- https://www.qt.io/blog/qt-5.15-extended-support-for-subscription-license-holders
Affected products (3)
- cpe:2.3:a:qt:qt:*:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:36:*:*:*:*:*:*:*
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