CVE-2021-20221

Description

An out-of-bounds heap buffer access issue was found in the ARM Generic Interrupt Controller emulator of QEMU up to and including qemu 4.2.0on aarch64 platform. The issue occurs because while writing an interrupt ID to the controller memory area, it is not masked to be 4 bits wide. It may lead to the said issue while updating controller state fields and their subsequent processing. A privileged guest user may use this flaw to crash the QEMU process on the host resulting in DoS scenario.

Status

Show unmaintained releases

Package	Ubuntu Release	Status
qemu-kvm	26.10 stonking	Not in release
	26.04 LTS resolute	Not in release
	25.10 questing	Not in release
	25.04 plucky	Not in release
	24.10 oracular	Not in release
	24.04 LTS noble	Not in release
	23.10 mantic	Not in release
	23.04 lunar	Not in release
	22.10 kinetic	Not in release
	22.04 LTS jammy	Not in release
	21.10 impish	Not in release
	21.04 hirsute	Not in release
	20.10 groovy	Not in release
	20.04 LTS focal	Not in release
	18.04 LTS bionic	Not in release
	16.04 LTS xenial	Not in release
	14.04 LTS trusty	Not in release
qemu	26.10 stonking	Fixed in 1:5.2+dfsg-6ubuntu2
	26.04 LTS resolute	Fixed in 1:5.2+dfsg-6ubuntu2
	25.10 questing	Fixed in 1:5.2+dfsg-6ubuntu2
	25.04 plucky	Fixed in 1:5.2+dfsg-6ubuntu2
	24.10 oracular	Fixed in 1:5.2+dfsg-6ubuntu2
	24.04 LTS noble	Fixed in 1:5.2+dfsg-6ubuntu2
	23.10 mantic	Fixed in 1:5.2+dfsg-6ubuntu2
	23.04 lunar	Fixed in 1:5.2+dfsg-6ubuntu2
	22.10 kinetic	Fixed in 1:5.2+dfsg-6ubuntu2
	22.04 LTS jammy	Fixed in 1:5.2+dfsg-6ubuntu2
	21.10 impish	Fixed in 1:5.2+dfsg-6ubuntu2
	21.04 hirsute	Fixed in 1:5.2+dfsg-6ubuntu2
	20.10 groovy	Fixed in 1:5.0-5ubuntu9.9
	20.04 LTS focal	Fixed in 1:4.2-3ubuntu6.17
	18.04 LTS bionic	Fixed in 1:2.11+dfsg-1ubuntu7.37
	16.04 LTS xenial	Fixed in 1:2.5+dfsg-5ubuntu10.51+esm4
	14.04 LTS trusty	Fixed in 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	Upstream: https://git.qemu.org/?p=qemu.git;a=commit;h=edfe2eb4360cde4ed5d95bda7777edcb3510f76a

Severity score breakdown

CVSS version: CVSS v3.0

Base score 6.0 · Medium

Base metrics

Parameter	Value
Attack vector	Local
Attack complexity	Low
Privileges required	High
User interaction	None
Scope	Changed
Confidentiality impact	None
Integrity impact	None
Availability impact	High

Scores

Parameter	Value
Base score	6.0 · Medium
Exploitability score	-
Impact score	-

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

References

Related Ubuntu Security Notices (USN)

USN-5010-1
QEMU vulnerabilities
15 July 2021

USN-8412-1
QEMU vulnerabilities
9 June 2026