CVE-2021-20255

Publication date 9 March 2021

Last updated 11 November 2024

Ubuntu priority

Cvss 3 Severity Score

A stack overflow via an infinite recursion vulnerability was found in the eepro100 i8255x device emulator of QEMU. This issue occurs while processing controller commands due to a DMA reentry issue. This flaw allows a guest user or process to consume CPU cycles or crash the QEMU process on the host, resulting in a denial of service. The highest threat from this vulnerability is to system availability.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
qemu	24.10 oracular	Vulnerable, fix deferred
	24.04 LTS noble	Vulnerable, fix deferred
	23.10 mantic	Ignored end of life, was deferred
	23.04 lunar	Ignored end of life, was deferred
	22.10 kinetic	Ignored end of life, was deferred
	22.04 LTS jammy	Vulnerable, fix deferred
	21.10 impish	Ignored end of life
	21.04 hirsute	Ignored end of life
	20.10 groovy	Ignored end of life
	20.04 LTS focal	Vulnerable, fix deferred
	18.04 LTS bionic	Vulnerable, fix deferred
	16.04 LTS xenial	Vulnerable, fix deferred
	14.04 LTS trusty	Ignored end of ESM support, was deferred
qemu-kvm	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

Notes

mdeslaur

as of 2023-11-30, proposed patch has not been commited upstream

bruce-cable

as of 2024-11-11, proposed patch not committed

Severity score breakdown

Parameter	Value
Base score	5.5 · Medium
Attack vector	Local
Attack complexity	Low
Privileges required	Low
User interaction	None
Scope	Unchanged
Confidentiality	None
Integrity impact	None
Availability impact	High
Vector	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H