CVE-2021-4207

A flaw was found in the QXL display device emulation in QEMU. A double fetch of guest controlled values cursor->header.width and cursor->header.height can lead to the allocation of a small cursor object followed by a subsequent heap-based buffer overflow. A malicious privileged guest user could use this flaw to crash the QEMU process on the host or potentially execute arbitrary code within the context of the QEMU process.

Releases of Red Hat OpenStack Platform 15 and newer consume fixes directly from the Red Hat Enterprise Linux 8 Advanced Virtualization repository. A future update may address this issue in Red Hat Enterprise Linux 8 and RHEL 8 Advanced Virtualization. The versions of qemu-kvm as shipped with Red Hat Enterprise Linux 9 are not affected by this flaw as they do not include support for QXL display device emulation.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.