Bug 2468124 (CVE-2026-43329) - CVE-2026-43329 kernel: netfilter: flowtable: strictly check for maximum number of actions
Summary: CVE-2026-43329 kernel: netfilter: flowtable: strictly check for maximum numbe...
Keywords:
Status: NEW
Alias: CVE-2026-43329
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
high
high
Target Milestone: ---
Assignee: Product Security DevOps Team
QA Contact:
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2026-05-08 14:05 UTC by OSIDB Bzimport
Modified: 2026-07-06 14:26 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-2026:23329 0 None None None 2026-06-04 14:53:44 UTC
Red Hat Product Errata RHSA-2026:26427 0 None None None 2026-06-16 18:55:34 UTC
Red Hat Product Errata RHSA-2026:26428 0 None None None 2026-06-16 18:29:40 UTC
Red Hat Product Errata RHSA-2026:27713 0 None None None 2026-06-22 05:01:30 UTC
Red Hat Product Errata RHSA-2026:30848 0 None None None 2026-06-29 04:56:23 UTC
Red Hat Product Errata RHSA-2026:33215 0 None None None 2026-06-29 19:23:59 UTC
Red Hat Product Errata RHSA-2026:33899 0 None None None 2026-07-01 00:15:54 UTC
Red Hat Product Errata RHSA-2026:33900 0 None None None 2026-07-01 00:13:38 UTC
Red Hat Product Errata RHSA-2026:34094 0 None None None 2026-07-01 08:59:06 UTC
Red Hat Product Errata RHSA-2026:34095 0 None None None 2026-07-01 08:40:58 UTC
Red Hat Product Errata RHSA-2026:35863 0 None None None 2026-07-06 04:51:32 UTC
Red Hat Product Errata RHSA-2026:35896 0 None None None 2026-07-06 14:26:46 UTC

Description OSIDB Bzimport 2026-05-08 14:05:41 UTC 
In the Linux kernel, the following vulnerability has been resolved:

netfilter: flowtable: strictly check for maximum number of actions

The maximum number of flowtable hardware offload actions in IPv6 is:

* ethernet mangling (4 payload actions, 2 for each ethernet address)
* SNAT (4 payload actions)
* DNAT (4 payload actions)
* Double VLAN (4 vlan actions, 2 for popping vlan, and 2 for pushing)
  for QinQ.
* Redirect (1 action)

Which makes 17, while the maximum is 16. But act_ct supports for tunnels
actions too. Note that payload action operates at 32-bit word level, so
mangling an IPv6 address takes 4 payload actions.

Update flow_action_entry_next() calls to check for the maximum number of
supported actions.

While at it, rise the maximum number of actions per flow from 16 to 24
so this works fine with IPv6 setups.
Comment 1 Alexander B 2026-05-15 10:52:36 UTC 
Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-43329.mbox
Comment 8 errata-xmlrpc 2026-06-04 14:53:43 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10

Via RHSA-2026:23329 https://access.redhat.com/errata/RHSA-2026:23329
Comment 9 errata-xmlrpc 2026-06-16 18:29:39 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2026:26428 https://access.redhat.com/errata/RHSA-2026:26428
Comment 10 errata-xmlrpc 2026-06-16 18:55:33 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2026:26427 https://access.redhat.com/errata/RHSA-2026:26427
Comment 11 errata-xmlrpc 2026-06-22 05:01:28 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions

Via RHSA-2026:27713 https://access.redhat.com/errata/RHSA-2026:27713
Comment 14 errata-xmlrpc 2026-06-29 04:56:22 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2026:30848 https://access.redhat.com/errata/RHSA-2026:30848
Comment 15 errata-xmlrpc 2026-06-29 19:23:58 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10.0 Extended Update Support

Via RHSA-2026:33215 https://access.redhat.com/errata/RHSA-2026:33215
Comment 16 errata-xmlrpc 2026-07-01 00:13:37 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions

Via RHSA-2026:33900 https://access.redhat.com/errata/RHSA-2026:33900
Comment 17 errata-xmlrpc 2026-07-01 00:15:53 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-2026:33899 https://access.redhat.com/errata/RHSA-2026:33899
Comment 18 errata-xmlrpc 2026-07-01 08:40:57 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions

Via RHSA-2026:34095 https://access.redhat.com/errata/RHSA-2026:34095
Comment 19 errata-xmlrpc 2026-07-01 08:59:05 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.6 Extended Update Support

Via RHSA-2026:34094 https://access.redhat.com/errata/RHSA-2026:34094
Comment 20 errata-xmlrpc 2026-07-06 04:51:31 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-2026:35863 https://access.redhat.com/errata/RHSA-2026:35863
Comment 21 errata-xmlrpc 2026-07-06 14:26:45 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-2026:35896 https://access.redhat.com/errata/RHSA-2026:35896
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