Bug 2403545 (CVE-2025-39964)

Summary:	CVE-2025-39964 kernel: crypto: af_alg - Disallow concurrent writes in af_alg_sendmsg
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security DevOps Team <prodsec-dev>
Status:	NEW ---	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	cchiang, 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 race condition was found in the Linux kernel cryptographic user API, AF_ALG in the way concurrent writes to the same AF_ALG socket are handled. Interleaved data and inconsistent internal socket state may result. A local user could use this flaw to crash the system or corrupt cryptographic operation results, causing a denial of service or data integrity issues.	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 2025-10-13 14:01:33 UTC

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

crypto: af_alg - Disallow concurrent writes in af_alg_sendmsg

Issuing two writes to the same af_alg socket is bogus as the
data will be interleaved in an unpredictable fashion.  Furthermore,
concurrent writes may create inconsistencies in the internal
socket state.

Disallow this by adding a new ctx->write field that indiciates
exclusive ownership for writing.

Comment 1 Jon Moroney 2025-10-13 16:01:31 UTC Comment hidden (spam)

This comment was flagged as spam, view the edit history to see the original text if required.

Comment 5 Jon Orris 2026-09-22 19:30:08 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2026:70403 https://access.redhat.com/errata/RHSA-2026:70403

Comment 6 Jon Orris 2026-09-22 20:20:58 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2026:70402 https://access.redhat.com/errata/RHSA-2026:70402

Comment 7 Jon Orris 2026-09-23 03:56:07 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10

Via RHSA-2026:70498 https://access.redhat.com/errata/RHSA-2026:70498

Comment 8 Jon Orris 2026-09-23 20:29:18 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2026:70459 https://access.redhat.com/errata/RHSA-2026:70459

Comment 9 Jon Orris 2026-09-24 05:40:32 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10.0 Extended Update Support

Via RHSA-2026:71326 https://access.redhat.com/errata/RHSA-2026:71326

Comment 10 Jon Orris 2026-09-24 05:58:35 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.6 Extended Update Support

Via RHSA-2026:71327 https://access.redhat.com/errata/RHSA-2026:71327

Comment 11 Jon Orris 2026-09-24 10:34:24 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-2026:71565 https://access.redhat.com/errata/RHSA-2026:71565

Comment 12 Jon Orris 2026-09-24 11:51:04 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 Extended Update Support Long-Life Add-On

Via RHSA-2026:71592 https://access.redhat.com/errata/RHSA-2026:71592

Comment 13 Jon Orris 2026-09-24 12:42:13 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions
  Red Hat Enterprise Linux 8.8 Telecommunications Update Service

Via RHSA-2026:71594 https://access.redhat.com/errata/RHSA-2026:71594

Comment 14 Jon Orris 2026-09-24 12:54:41 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions

Via RHSA-2026:71606 https://access.redhat.com/errata/RHSA-2026:71606

Comment 15 Jon Orris 2026-09-24 13:43:20 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions

Via RHSA-2026:71569 https://access.redhat.com/errata/RHSA-2026:71569

Comment 16 Jon Orris 2026-09-24 13:46:35 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions

Via RHSA-2026:71601 https://access.redhat.com/errata/RHSA-2026:71601

Comment 17 Jon Orris 2026-09-24 16:16:48 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7 Extended Lifecycle Support

Via RHSA-2026:71657 https://access.redhat.com/errata/RHSA-2026:71657

Comment 18 Jon Orris 2026-09-24 22:30:35 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7 Extended Lifecycle Support

Via RHSA-2026:71687 https://access.redhat.com/errata/RHSA-2026:71687

Comment 19 Jon Orris 2026-09-25 18:00:43 UTC

This issue has been addressed in the following products:

  NVIDIA for RHEL 10

Via RHSA-2026:72059 https://access.redhat.com/errata/RHSA-2026:72059

Comment 20 Jon Orris 2026-09-30 07:46:24 UTC

This issue has been addressed in the following products:

  NVIDIA for RHEL 10

Via RHSA-2026:73788 https://access.redhat.com/errata/RHSA-2026:73788