Bug 2382581 (CVE-2025-38352)

Summary:	CVE-2025-38352 kernel: posix-cpu-timers: fix race between handle_posix_cpu_timers() and posix_cpu_timer_del()
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security DevOps Team <prodsec-dev>
Status:	NEW ---	QA Contact:
Severity:	high	Docs Contact:
Priority:	high
Version:	unspecified	CC:	dwb7, michael.h.hall-1
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	---
Doc Text:	A race condition was found in the Linux kernel’s POSIX CPU timer handling, where handle_posix_cpu_timers() may run concurrently with posix_cpu_timer_del() on an exiting task which could result in use-after-free scenarios. An attacker with local user access could use this flaw to crash or escalate their privileges on a system.	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:

Description OSIDB Bzimport 2025-07-22 09:01:21 UTC

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

posix-cpu-timers: fix race between handle_posix_cpu_timers() and posix_cpu_timer_del()

If an exiting non-autoreaping task has already passed exit_notify() and
calls handle_posix_cpu_timers() from IRQ, it can be reaped by its parent
or debugger right after unlock_task_sighand().

If a concurrent posix_cpu_timer_del() runs at that moment, it won't be
able to detect timer->it.cpu.firing != 0: cpu_timer_task_rcu() and/or
lock_task_sighand() will fail.

Add the tsk->exit_state check into run_posix_cpu_timers() to fix this.

This fix is not needed if CONFIG_POSIX_CPU_TIMERS_TASK_WORK=y, because
exit_task_work() is called before exit_notify(). But the check still
makes sense, task_work_add(&tsk->posix_cputimers_work.work) will fail
anyway in this case.

Comment 1 Michal Findra 2025-07-22 12:10:44 UTC

Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2025072229-CVE-2025-38352-f1de@gregkh/T

Comment 3 Dave B 2025-09-05 20:15:50 UTC

https://cybersecuritynews.com/cisa-linux-kernel-race-condition-vulnerability/
...
In response to confirmed “in-the-wild” exploitation, CISA’s addition to the KEV catalog triggers a binding operational directive for federal agencies.
...

Comment 6 errata-xmlrpc 2025-09-08 13:34:36 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2025:15472 https://access.redhat.com/errata/RHSA-2025:15472

Comment 7 errata-xmlrpc 2025-09-08 13:54:42 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2025:15471 https://access.redhat.com/errata/RHSA-2025:15471

Comment 10 errata-xmlrpc 2025-09-10 15:52:08 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7 Extended Lifecycle Support

Via RHSA-2025:15646 https://access.redhat.com/errata/RHSA-2025:15646

Comment 11 errata-xmlrpc 2025-09-10 16:13:50 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support
  Red Hat Enterprise Linux 8.6 Update Services for SAP Solutions
  Red Hat Enterprise Linux 8.6 Telecommunications Update Service

Via RHSA-2025:15647 https://access.redhat.com/errata/RHSA-2025:15647

Comment 12 errata-xmlrpc 2025-09-10 16:18:01 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7 Extended Lifecycle Support

Via RHSA-2025:15648 https://access.redhat.com/errata/RHSA-2025:15648

Comment 13 errata-xmlrpc 2025-09-10 17:14:53 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions

Via RHSA-2025:15649 https://access.redhat.com/errata/RHSA-2025:15649

Comment 14 errata-xmlrpc 2025-09-10 18:23:11 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.2 Advanced Update Support

Via RHSA-2025:15656 https://access.redhat.com/errata/RHSA-2025:15656

Comment 15 errata-xmlrpc 2025-09-10 18:48:28 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions

Via RHSA-2025:15657 https://access.redhat.com/errata/RHSA-2025:15657

Comment 16 errata-xmlrpc 2025-09-10 20:42:27 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions

Via RHSA-2025:15658 https://access.redhat.com/errata/RHSA-2025:15658

Comment 17 errata-xmlrpc 2025-09-11 01:48:58 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support
  Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On

Via RHSA-2025:15660 https://access.redhat.com/errata/RHSA-2025:15660

Comment 18 errata-xmlrpc 2025-09-11 03:14:42 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2025:15661 https://access.redhat.com/errata/RHSA-2025:15661

Comment 19 errata-xmlrpc 2025-09-11 03:38:38 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10

Via RHSA-2025:15662 https://access.redhat.com/errata/RHSA-2025:15662

Comment 20 errata-xmlrpc 2025-09-11 06:28:09 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions

Via RHSA-2025:15669 https://access.redhat.com/errata/RHSA-2025:15669

Comment 21 errata-xmlrpc 2025-09-11 06:36:10 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.4 Extended Update Support

Via RHSA-2025:15668 https://access.redhat.com/errata/RHSA-2025:15668

Comment 22 errata-xmlrpc 2025-09-11 07:35:29 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions

Via RHSA-2025:15670 https://access.redhat.com/errata/RHSA-2025:15670

Comment 23 errata-xmlrpc 2025-09-15 13:27:13 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2025:15798 https://access.redhat.com/errata/RHSA-2025:15798

Comment 24 errata-xmlrpc 2025-09-16 08:04:28 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2025:15921 https://access.redhat.com/errata/RHSA-2025:15921

Comment 25 errata-xmlrpc 2025-09-16 09:02:09 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions

Via RHSA-2025:15931 https://access.redhat.com/errata/RHSA-2025:15931

Comment 26 errata-xmlrpc 2025-09-16 09:03:05 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.4 Extended Update Support

Via RHSA-2025:15932 https://access.redhat.com/errata/RHSA-2025:15932

Comment 27 errata-xmlrpc 2025-09-16 09:04:11 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions

Via RHSA-2025:15933 https://access.redhat.com/errata/RHSA-2025:15933

Comment 28 errata-xmlrpc 2025-09-16 17:48:08 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions

Via RHSA-2025:16008 https://access.redhat.com/errata/RHSA-2025:16008

Comment 29 errata-xmlrpc 2025-09-17 07:24:30 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.6 Update Services for SAP Solutions

Via RHSA-2025:16045 https://access.redhat.com/errata/RHSA-2025:16045