CVE-2021-4206

A flaw was found in the QXL display device emulation in QEMU. An integer overflow in the cursor_alloc() function can lead to the allocation of a small cursor object followed by a subsequent heap-based buffer overflow. This flaw allows a malicious privileged guest user to crash the QEMU process on the host or potentially execute arbitrary code within the context of the QEMU process.

• CWE-190
• CWE-120
• CWE-131
• CWE-190

• https://bugzilla.redhat.com/show_bug.cgi?id=2036998Issue Tracking, Third Party Advisory
• https://lists.debian.org/debian-lts-announce/2022/09/msg00008.htmlMailing List, Third Party Advisory
• https://security.gentoo.org/glsa/202208-27Third Party Advisory
• https://starlabs.sg/advisories/21-4206/Exploit, Third Party Advisory
• https://www.debian.org/security/2022/dsa-5133Third Party Advisory
• https://bugzilla.redhat.com/show_bug.cgi?id=2036998Issue Tracking, Third Party Advisory
• https://lists.debian.org/debian-lts-announce/2022/09/msg00008.htmlMailing List, Third Party Advisory
• https://security.gentoo.org/glsa/202208-27Third Party Advisory
• https://security.netapp.com/advisory/ntap-20250321-0010/
• https://starlabs.sg/advisories/21-4206/Exploit, Third Party Advisory
• https://www.debian.org/security/2022/dsa-5133Third Party Advisory

Published

Apr 29, 2022

Last Modified

Jun 17, 2026

Status

Modified

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