Bug 2510890 (CVE-2026-64564)

Summary: CVE-2026-64564 kernel: sctp: don't free the ASCONF's own transport in DEL-IP processing
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedCC: akhatavk, akito5623, aos-team-art-private, asdas, dpaolell, jdelft, jupierce, lgarciaa, mbiarnes, ppalepu, ppostler, prdhamdh, rhel-process-autobot, sghai, sidsharm, suppawar, vlaad, 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 Stream Control Transmission Protocol (SCTP) implementation within the Linux kernel. A remote attacker could send a specially crafted sequence of ASCONF (Add IP Address Configuration) chunks, including DEL-IP (Delete IP Address) parameters, to trigger a use-after-free condition. This memory corruption could lead to a system crash, resulting in a denial of service, and potentially allow for arbitrary code execution.
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Clone Of: Environment:
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:

Description OSIDB Bzimport 2026-08-04 07:02:12 UTC
In the Linux kernel, the following vulnerability has been resolved:

sctp: don't free the ASCONF's own transport in DEL-IP processing

sctp_process_asconf() caches the transport the ASCONF chunk is processed
against in asconf->transport (== chunk->transport, set once in sctp_rcv()).
For an ASCONF located through its Address Parameter by
__sctp_rcv_asconf_lookup(), that cached transport corresponds to the
Address Parameter, which need not be the packet's source address.

sctp_process_asconf_param() rejects a DEL-IP for the packet source address
(ADDIP D8, SCTP_ERROR_DEL_SRC_IP), but nothing protects asconf->transport.
A single ASCONF can therefore carry, in order:

    [Address Parameter L] [DEL-IP L] [DEL-IP 0.0.0.0]

where L differs from the source. The DEL-IP for L passes the D8 check and
calls sctp_assoc_rm_peer() on the transport that asconf->transport still
points at, freeing it (RCU-deferred). The following wildcard DEL-IP then
reuses the now-dangling asconf->transport in sctp_assoc_set_primary() and
sctp_assoc_del_nonprimary_peers(): set_primary() dereferences the freed
transport (->ipaddr, ->state) and plants the dangling pointer into
asoc->peer.primary_path / active_path, and del_nonprimary_peers(), keeping
only the pointer that is no longer on the list, removes every real
transport, leaving the association with a transport_count of 0 and
primary_path/active_path pointing at freed memory.

Reject a DEL-IP that targets the transport the ASCONF is being processed
against, mirroring the existing source-address guard, so the wildcard
branch can never reuse a freed transport.

Comment 1 Mauro Matteo Cascella 2026-08-04 08:59:08 UTC
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026080404-CVE-2026-64564-6762@gregkh/T

Comment 4 Jon Orris 2026-09-21 00:56:39 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10.0 Extended Update Support

Via RHSA-2026:69089 https://access.redhat.com/errata/RHSA-2026:69089

Comment 6 Jon Orris 2026-09-22 03:33:46 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-2026:69837 https://access.redhat.com/errata/RHSA-2026:69837

Comment 7 Jon Orris 2026-09-22 07:16:35 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-2026:69874 https://access.redhat.com/errata/RHSA-2026:69874

Comment 8 Jon Orris 2026-09-22 08:28:20 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-2026:69906 https://access.redhat.com/errata/RHSA-2026:69906

Comment 9 Jon Orris 2026-09-22 10:44:59 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions

Via RHSA-2026:69908 https://access.redhat.com/errata/RHSA-2026:69908

Comment 10 Jon Orris 2026-09-22 16:05:05 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7 Extended Lifecycle Support

Via RHSA-2026:70290 https://access.redhat.com/errata/RHSA-2026:70290

Comment 11 Jon Orris 2026-09-22 16:05:36 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7 Extended Lifecycle Support

Via RHSA-2026:70308 https://access.redhat.com/errata/RHSA-2026:70308

Comment 12 Jon Orris 2026-09-23 00:24:59 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions

Via RHSA-2026:70483 https://access.redhat.com/errata/RHSA-2026:70483

Comment 13 Jon Orris 2026-09-23 01:39:21 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions

Via RHSA-2026:70482 https://access.redhat.com/errata/RHSA-2026:70482

Comment 14 Jon Orris 2026-09-23 02:24:17 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.6 Extended Update Support

Via RHSA-2026:70484 https://access.redhat.com/errata/RHSA-2026:70484

Comment 15 Jon Orris 2026-09-23 18:08:43 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2026:71016 https://access.redhat.com/errata/RHSA-2026:71016

Comment 16 Jon Orris 2026-09-24 01:02:40 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2026:71213 https://access.redhat.com/errata/RHSA-2026:71213

Comment 17 Jon Orris 2026-09-24 03:01:04 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10

Via RHSA-2026:71233 https://access.redhat.com/errata/RHSA-2026:71233

Comment 18 Jon Orris 2026-09-24 05:52:43 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2026:71232 https://access.redhat.com/errata/RHSA-2026:71232