Bug 2461757 (CVE-2026-31684) - CVE-2026-31684 kernel: net: sched: act_csum: validate nested VLAN headers
Summary: CVE-2026-31684 kernel: net: sched: act_csum: validate nested VLAN headers
Keywords:
Status: NEW
Alias: CVE-2026-31684
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
medium
medium
Target Milestone: ---
Assignee: Product Security DevOps Team
QA Contact:
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2026-04-25 09:01 UTC by OSIDB Bzimport
Modified: 2026-07-29 22:42 UTC (History)
2 users (show)

Fixed In Version:
Clone Of:
Environment:
Last Closed:
Embargoed:


Attachments (Terms of Use)


Links
System ID Private Priority Status Summary Last Updated
Red Hat Product Errata RHSA-2026:21556 0 None None None 2026-05-28 01:24:01 UTC
Red Hat Product Errata RHSA-2026:21557 0 None None None 2026-05-28 01:19:57 UTC
Red Hat Product Errata RHSA-2026:21706 0 None None None 2026-05-28 08:26:00 UTC
Red Hat Product Errata RHSA-2026:21745 0 None None None 2026-05-28 13:26:27 UTC
Red Hat Product Errata RHSA-2026:40068 0 None None None 2026-07-15 15:54:12 UTC
Red Hat Product Errata RHSA-2026:41234 0 None None None 2026-07-17 12:49:21 UTC
Red Hat Product Errata RHSA-2026:41235 0 None None None 2026-07-17 13:02:20 UTC
Red Hat Product Errata RHSA-2026:43231 0 None None None 2026-07-22 06:23:45 UTC
Red Hat Product Errata RHSA-2026:44385 0 None None None 2026-07-23 11:56:59 UTC
Red Hat Product Errata RHSA-2026:44694 0 None None None 2026-07-23 20:55:04 UTC
Red Hat Product Errata RHSA-2026:47632 0 None None None 2026-07-29 00:52:05 UTC
Red Hat Product Errata RHSA-2026:47633 0 None None None 2026-07-29 01:06:29 UTC
Red Hat Product Errata RHSA-2026:47739 0 None None None 2026-07-29 22:42:24 UTC
Red Hat Product Errata RHSA-2026:47869 0 None None None 2026-07-29 13:30:52 UTC

Description OSIDB Bzimport 2026-04-25 09:01:33 UTC
In the Linux kernel, the following vulnerability has been resolved:

net: sched: act_csum: validate nested VLAN headers

tcf_csum_act() walks nested VLAN headers directly from skb->data when an
skb still carries in-payload VLAN tags. The current code reads
vlan->h_vlan_encapsulated_proto and then pulls VLAN_HLEN bytes without
first ensuring that the full VLAN header is present in the linear area.

If only part of an inner VLAN header is linearized, accessing
h_vlan_encapsulated_proto reads past the linear area, and the following
skb_pull(VLAN_HLEN) may violate skb invariants.

Fix this by requiring pskb_may_pull(skb, VLAN_HLEN) before accessing and
pulling each nested VLAN header. If the header still is not fully
available, drop the packet through the existing error path.

Comment 4 errata-xmlrpc 2026-05-28 01:19:55 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10

Via RHSA-2026:21557 https://access.redhat.com/errata/RHSA-2026:21557

Comment 5 errata-xmlrpc 2026-05-28 01:24:00 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2026:21556 https://access.redhat.com/errata/RHSA-2026:21556

Comment 6 errata-xmlrpc 2026-05-28 08:25:59 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2026:21706 https://access.redhat.com/errata/RHSA-2026:21706

Comment 7 errata-xmlrpc 2026-05-28 13:26:26 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2026:21745 https://access.redhat.com/errata/RHSA-2026:21745

Comment 8 errata-xmlrpc 2026-07-15 15:54:11 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-2026:40068 https://access.redhat.com/errata/RHSA-2026:40068

Comment 9 errata-xmlrpc 2026-07-17 12:49:20 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7 Extended Lifecycle Support

Via RHSA-2026:41234 https://access.redhat.com/errata/RHSA-2026:41234

Comment 10 errata-xmlrpc 2026-07-17 13:02:19 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7 Extended Lifecycle Support

Via RHSA-2026:41235 https://access.redhat.com/errata/RHSA-2026:41235

Comment 11 errata-xmlrpc 2026-07-22 06:23:44 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions

Via RHSA-2026:43231 https://access.redhat.com/errata/RHSA-2026:43231

Comment 12 errata-xmlrpc 2026-07-23 11:56:58 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.6 Extended Update Support

Via RHSA-2026:44385 https://access.redhat.com/errata/RHSA-2026:44385

Comment 13 errata-xmlrpc 2026-07-23 20:55:03 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10.0 Extended Update Support

Via RHSA-2026:44694 https://access.redhat.com/errata/RHSA-2026:44694

Comment 14 errata-xmlrpc 2026-07-29 00:52:04 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions

Via RHSA-2026:47632 https://access.redhat.com/errata/RHSA-2026:47632

Comment 15 errata-xmlrpc 2026-07-29 01:06:28 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-2026:47633 https://access.redhat.com/errata/RHSA-2026:47633

Comment 16 errata-xmlrpc 2026-07-29 13:30:51 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-2026:47869 https://access.redhat.com/errata/RHSA-2026:47869

Comment 17 errata-xmlrpc 2026-07-29 22:42:23 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions

Via RHSA-2026:47739 https://access.redhat.com/errata/RHSA-2026:47739


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