Bug 2492426 (CVE-2026-53020)

Summary:	CVE-2026-53020 kernel: um: Fix potential race condition in TLB sync
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security <prodsec-ir-bot>
Status:	NEW ---	QA Contact:
Severity:	unspecified	Docs Contact:
Priority:	unspecified
Version:	unspecified	CC:	rhel-process-autobot, watson-tool-maintainers
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	---
Doc Text:	A flaw was found in the Linux kernel. A race condition can occur during Translation Lookaside Buffer (TLB) synchronization when the page table is traversed and modified without properly holding the necessary page table lock. This vulnerability may allow for unpredictable system behavior or instability due to concurrent access to shared resources.	Story Points:	---
Clone Of:		Environment:
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Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description OSIDB Bzimport 2026-06-24 18:11:26 UTC

In the Linux kernel, the following vulnerability has been resolved:

um: Fix potential race condition in TLB sync

During the TLB sync, we need to traverse and modify the page table,
so we should hold the page table lock. Since full SMP support for
threads within the same process is still missing, let's disable the
split page table lock for simplicity.

Comment 1 Mauro Matteo Cascella 2026-06-26 11:51:21 UTC

Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026062452-CVE-2026-53020-6e28@gregkh/T