Bug 2559182

Summary:	CVE-2026-79610 xen: Xen: Host privilege escalation via stale grant table pointers [fedora-all]
Product:	[Fedora] Fedora	Reporter:	Oleg Sushchenko <osushche>
Component:	xen	Assignee:	Michael Young <m.a.young>
Status:	ON_QA ---	QA Contact:	Fedora Extras Quality Assurance <extras-qa>
Severity:	high	Docs Contact:
Priority:	high
Version:	rawhide	CC:	jforbes, m.a.young
Target Milestone:	---	Keywords:	Security, SecurityTracking
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:	{"flaws": ["53c3108b-a166-476d-a7af-a3cae81832d0"]}
Fixed In Version:		Doc Type:	---
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:		Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:
Bug Blocks:	2550648

Description Oleg Sushchenko 2026-10-22 17:25:54 UTC

Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.

XSA-501 was about issues with v1 -> v2 and v2 -> v1 changes racing certain
other grant table operations.  Sadly a v2 -> v1 -> v2 change has yet
another effect which wasn't accounted for: During the first change, status
pages would be freed.  During the second change they would be allocated
again.  Hence across the full pair of change the addresses of the status
pages may change, rendering stale previously calculated pointers into the
status array.

Comment 1 Fedora Update System 2026-10-30 23:27:41 UTC

FEDORA-2026-2b73a60d2c (xen-4.20.4-4.fc43) has been submitted as an update to Fedora 43.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-2b73a60d2c

Comment 2 Fedora Update System 2026-10-31 02:44:22 UTC

FEDORA-2026-2b73a60d2c has been pushed to the Fedora 43 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2026-2b73a60d2c`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-2b73a60d2c

See also https://fedoraproject.org/wiki/QA:Updates_Testing for more information on how to test updates.

Comment 3 Fedora Update System 2026-11-06 03:33:42 UTC

FEDORA-2026-94fa41e927 has been pushed to the Fedora 43 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2026-94fa41e927`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-94fa41e927

See also https://fedoraproject.org/wiki/QA:Updates_Testing for more information on how to test updates.