Bug 2406202 (CVE-2025-40021)

Summary:	CVE-2025-40021 kernel: tracing: dynevent: Add a missing lockdown check on dynevent
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security DevOps Team <prodsec-dev>
Status:	NEW ---	QA Contact:
Severity:	low	Docs Contact:
Priority:	low
Version:	unspecified	CC:	rhel-process-autobot, watson-tool-maintainers
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
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Fixed In Version:		Doc Type:	---
Doc Text:	A missing security check was found in the Linux kernel's tracing subsystem in the dynamic events interface on tracefs. A local user can bypass kernel lockdown restrictions by using the dynamic_events interface to create kprobes or uprobes, since this interface lacks the lockdown validation present in the equivalent kprobe_events and uprobe_events interfaces. This allows unauthorized modification of kernel tracing state on systems where lockdown should prevent such operations.	Story Points:	---
Clone Of:		Environment:
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Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description OSIDB Bzimport 2025-10-24 13:01:29 UTC

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

tracing: dynevent: Add a missing lockdown check on dynevent

Since dynamic_events interface on tracefs is compatible with
kprobe_events and uprobe_events, it should also check the lockdown
status and reject if it is set.

Comment 1 Keith Grant 2025-10-24 13:43:34 UTC

Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2025102403-CVE-2025-40021-fbe1@gregkh/T