CVE-2022-33745

Publication date 26 July 2022

Last updated 11 July 2025

Ubuntu priority

Cvss 3 Severity Score

Description

insufficient TLB flush for x86 PV guests in shadow mode For migration as well as to work around kernels unaware of L1TF (see XSA-273), PV guests may be run in shadow paging mode. To address XSA-401, code was moved inside a function in Xen. This code movement missed a variable changing meaning / value between old and new code positions. The now wrong use of the variable did lead to a wrong TLB flush condition, omitting flushes where such are necessary.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
xen	25.10 questing	Needs evaluation
	25.04 plucky	Needs evaluation
	24.10 oracular	Ignored end of life, was needs-triage
	24.04 LTS noble	Needs evaluation
	23.10 mantic	Ignored end of life, was needs-triage
	23.04 lunar	Ignored end of life, was needs-triage
	22.10 kinetic	Ignored end of life, was needs-triage
	22.04 LTS jammy	Needs evaluation
	20.04 LTS focal	Needs evaluation
	18.04 LTS bionic	Needs evaluation
	16.04 LTS xenial	Needs evaluation
	14.04 LTS trusty	Not in release

Notes

mdeslaur

hypervisor packages are in universe. For issues in the hypervisor, add appropriate tags to each section, ex: Tags_xen: universe-binary

Severity score breakdown

Parameter	Value
Base score	8.8 · High
Attack vector	Local
Attack complexity	Low
Privileges required	Low
User interaction	None
Scope	Changed
Confidentiality	High
Integrity impact	High
Availability impact	High
Vector	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H