Bug 2439931 (CVE-2026-23204) - CVE-2026-23204 kernel: net/sched: cls_u32: use skb_header_pointer_careful()
Summary: CVE-2026-23204 kernel: net/sched: cls_u32: use skb_header_pointer_careful()
Keywords:
Status: NEW
Alias: CVE-2026-23204
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: 2026-02-14 17:03 UTC by OSIDB Bzimport
Modified: 2026-04-27 10:31 UTC (History)
0 users

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-2026:10108 0 None None None 2026-04-23 22:46:43 UTC
Red Hat Product Errata RHSA-2026:10756 0 None None None 2026-04-27 10:31:46 UTC
Red Hat Product Errata RHSA-2026:6036 0 None None None 2026-03-30 02:18:10 UTC
Red Hat Product Errata RHSA-2026:6037 0 None None None 2026-03-30 02:40:52 UTC
Red Hat Product Errata RHSA-2026:6153 0 None None None 2026-03-30 11:06:29 UTC
Red Hat Product Errata RHSA-2026:6632 0 None None None 2026-04-06 07:50:02 UTC
Red Hat Product Errata RHSA-2026:8342 0 None None None 2026-04-15 20:06:44 UTC
Red Hat Product Errata RHSA-2026:9112 0 None None None 2026-04-20 20:28:58 UTC
Red Hat Product Errata RHSA-2026:9512 0 None None None 2026-04-22 00:11:18 UTC
Red Hat Product Errata RHSA-2026:9513 0 None None None 2026-04-22 00:11:44 UTC
Red Hat Product Errata RHSA-2026:9514 0 None None None 2026-04-22 00:23:30 UTC
Red Hat Product Errata RHSA-2026:9515 0 None None None 2026-04-22 00:20:15 UTC
Red Hat Product Errata RHSA-2026:9643 0 None None None 2026-04-22 07:51:57 UTC
Red Hat Product Errata RHSA-2026:9644 0 None None None 2026-04-22 08:05:13 UTC
Red Hat Product Errata RHSA-2026:9835 0 None None None 2026-04-22 17:40:00 UTC
Red Hat Product Errata RHSA-2026:9836 0 None None None 2026-04-22 17:46:51 UTC
Red Hat Product Errata RHSA-2026:9870 0 None None None 2026-04-22 20:40:49 UTC

Description OSIDB Bzimport 2026-02-14 17:03:39 UTC 
In the Linux kernel, the following vulnerability has been resolved:

net/sched: cls_u32: use skb_header_pointer_careful()

skb_header_pointer() does not fully validate negative @offset values.

Use skb_header_pointer_careful() instead.

GangMin Kim provided a report and a repro fooling u32_classify():

BUG: KASAN: slab-out-of-bounds in u32_classify+0x1180/0x11b0
net/sched/cls_u32.c:221
Comment 1 TEJ RATHI 2026-02-16 06:36:43 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026021437-CVE-2026-23204-be85@gregkh/T
Comment 3 errata-xmlrpc 2026-03-30 02:18:10 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2026:6036 https://access.redhat.com/errata/RHSA-2026:6036
Comment 4 errata-xmlrpc 2026-03-30 02:40:51 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2026:6037 https://access.redhat.com/errata/RHSA-2026:6037
Comment 5 errata-xmlrpc 2026-03-30 11:06:28 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2026:6153 https://access.redhat.com/errata/RHSA-2026:6153
Comment 6 errata-xmlrpc 2026-04-06 07:50:01 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10

Via RHSA-2026:6632 https://access.redhat.com/errata/RHSA-2026:6632
Comment 7 errata-xmlrpc 2026-04-15 20:06:43 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10.0 Extended Update Support

Via RHSA-2026:8342 https://access.redhat.com/errata/RHSA-2026:8342
Comment 8 errata-xmlrpc 2026-04-20 20:28:57 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.6 Extended Update Support

Via RHSA-2026:9112 https://access.redhat.com/errata/RHSA-2026:9112
Comment 9 errata-xmlrpc 2026-04-22 00:11:17 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions

Via RHSA-2026:9512 https://access.redhat.com/errata/RHSA-2026:9512
Comment 10 errata-xmlrpc 2026-04-22 00:11:43 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.2 Advanced Update Support

Via RHSA-2026:9513 https://access.redhat.com/errata/RHSA-2026:9513
Comment 11 errata-xmlrpc 2026-04-22 00:20:14 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-2026:9515 https://access.redhat.com/errata/RHSA-2026:9515
Comment 12 errata-xmlrpc 2026-04-22 00:23:29 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-2026:9514 https://access.redhat.com/errata/RHSA-2026:9514
Comment 13 errata-xmlrpc 2026-04-22 07:51:57 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-2026:9643 https://access.redhat.com/errata/RHSA-2026:9643
Comment 14 errata-xmlrpc 2026-04-22 08:05:12 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions

Via RHSA-2026:9644 https://access.redhat.com/errata/RHSA-2026:9644
Comment 15 errata-xmlrpc 2026-04-22 17:39:59 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions

Via RHSA-2026:9835 https://access.redhat.com/errata/RHSA-2026:9835
Comment 16 errata-xmlrpc 2026-04-22 17:46:50 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions

Via RHSA-2026:9836 https://access.redhat.com/errata/RHSA-2026:9836
Comment 17 errata-xmlrpc 2026-04-22 20:40:48 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7 Extended Lifecycle Support

Via RHSA-2026:9870 https://access.redhat.com/errata/RHSA-2026:9870
Comment 18 errata-xmlrpc 2026-04-23 22:46:42 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.4 Extended Update Support

Via RHSA-2026:10108 https://access.redhat.com/errata/RHSA-2026:10108
Comment 20 errata-xmlrpc 2026-04-27 10:31:45 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7 Extended Lifecycle Support

Via RHSA-2026:10756 https://access.redhat.com/errata/RHSA-2026:10756
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