CVE-2021-4207

Publication date 29 April 2022

Last updated 9 June 2026

Ubuntu priority

Medium

Why this priority?

Cvss 3 Severity Score

8.2 · High

Score breakdown

Description

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.

Status

Package Ubuntu Release Status
qemu 26.04 LTS resolute
Fixed 1:6.2+dfsg-2ubuntu8
25.10 questing
Fixed 1:6.2+dfsg-2ubuntu8
25.04 plucky
Fixed 1:6.2+dfsg-2ubuntu8
24.10 oracular
Fixed 1:6.2+dfsg-2ubuntu8
24.04 LTS noble
Fixed 1:6.2+dfsg-2ubuntu8
23.10 mantic
Fixed 1:6.2+dfsg-2ubuntu8
23.04 lunar
Fixed 1:6.2+dfsg-2ubuntu8
22.10 kinetic
Fixed 1:6.2+dfsg-2ubuntu8
22.04 LTS jammy
Fixed 1:6.2+dfsg-2ubuntu6.2
21.10 impish
Fixed 1:6.0+dfsg-2expubuntu1.3
20.04 LTS focal
Fixed 1:4.2-3ubuntu6.23
18.04 LTS bionic
Fixed 1:2.11+dfsg-1ubuntu7.40
16.04 LTS xenial
Fixed 1:2.5+dfsg-5ubuntu10.51+esm4
14.04 LTS trusty
Fixed 2.0.0+dfsg-2ubuntu1.47+esm6

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Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package Patch details
qemu

Severity score breakdown

CVSS version: CVSS v3.0

Base score 8.2 · High

Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H

References

Related Ubuntu Security Notices (USN)

Other references

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