Bug 2418832 (CVE-2025-40240)

Summary:	CVE-2025-40240 kernel: sctp: avoid NULL dereference when chunk data buffer is missing
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	Keywords:	Security
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Hardware:	All
OS:	Linux
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oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
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Description OSIDB Bzimport 2025-12-04 16:03:06 UTC

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

sctp: avoid NULL dereference when chunk data buffer is missing

chunk->skb pointer is dereferenced in the if-block where it's supposed
to be NULL only.

chunk->skb can only be NULL if chunk->head_skb is not. Check for frag_list
instead and do it just before replacing chunk->skb. We're sure that
otherwise chunk->skb is non-NULL because of outer if() condition.

Comment 1 Alexander B 2025-12-05 15:29:30 UTC

Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2025120403-CVE-2025-40240-745a@gregkh/T

Comment 6 errata-xmlrpc 2026-01-12 02:37:13 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2026:0443 https://access.redhat.com/errata/RHSA-2026:0443

Comment 7 errata-xmlrpc 2026-01-12 03:27:52 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2026:0444 https://access.redhat.com/errata/RHSA-2026:0444

Comment 8 errata-xmlrpc 2026-01-12 04:42:30 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2026:0445 https://access.redhat.com/errata/RHSA-2026:0445

Comment 9 errata-xmlrpc 2026-01-12 09:10:52 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10

Via RHSA-2026:0453 https://access.redhat.com/errata/RHSA-2026:0453

Comment 10 errata-xmlrpc 2026-02-02 15:25:19 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10.0 Extended Update Support

Via RHSA-2026:1727 https://access.redhat.com/errata/RHSA-2026:1727

Comment 11 errata-xmlrpc 2026-02-11 11:50:51 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-2026:2535 https://access.redhat.com/errata/RHSA-2026:2535