CVE-2021-4206: Debian Linux

High severity, CVSS 8.2. EPSS: 0.8% chance of exploitation in the next 30 days.

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.

Affected products

• Debian Debian Linux: version 10.0 only; version 11.0 only
• Qemu Qemu: before 7.0.0 (fixed in 7.0.0)
• Red Hat Enterprise Linux: version 8.0 only

Published 2022-04-29. Last modified 2026-06-17.