CVE-2025-21958

linux: In the Linux kernel, the following vulnerability has been resolved: Revert "openvswitch: switch to per-action label...

CVE-2025-21958 is fixed in 36 products on 1 platform, first by DEBIAN-CVE-2025-21958, released April 1, 2025. It is not reported as exploited. Patch Radar priority: Routine.

Routine
CVSS
5.5
medium
Exploitation
None reported
No vendor assessment
CISA KEV
Not listed
Not in the Known Exploited Vulnerabilities catalog
EPSS
0.0016
4th percentile

In the Linux kernel, the following vulnerability has been resolved: Revert "openvswitch: switch to per-action label counting in conntrack" Currently, ovs_ct_set_labels() is only called for confirmed conntrack entries (ct) within ovs_ct_commit(). However, if the conntrack entry does not have the labels_ext extension, attempting to allocate it in ovs_ct_get_conn_labels() for a confirmed entry triggers a warning in nf_ct_ext_add(): WARN_ON(nf_ct_is_confirmed(ct)); This happens when the conntrack entry is created externally before OVS increments net->ct.labels_used. The issue has become more likely since commit fcb1aa5163b1 ("openvswitch: switch to per-action label counting in conntrack"), which changed to use per-action label counting and increment net->ct.labels_used when a flow with ct action is added. Since there’s no straightforward way to fully resolve this issue at the moment, this reverts the commit to avoid breaking existing use cases.

Where it's fixed

ProductFixed inFixReleased
Linux
kernel-uek · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-core · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-core · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-debug · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-debug · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-debug-core · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-debug-core · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-debug-devel · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-debug-devel · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-debug-modules · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-debug-modules · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-debug-modules-core · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-debug-modules-core · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-debug-modules-deprecated · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-debug-modules-deprecated · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-debug-modules-desktop · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-debug-modules-desktop · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-debug-modules-extra · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-debug-modules-extra · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-debug-modules-extra-netfilter · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-debug-modules-extra-netfilter · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-debug-modules-usb · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-debug-modules-usb · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-debug-modules-wireless · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-debug-modules-wireless · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-devel · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-devel · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-doc · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-doc · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-modules · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-modules · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-modules-core · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-modules-core · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-modules-deprecated · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-modules-deprecated · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-modules-desktop · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-modules-desktop · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-modules-extra · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-modules-extra · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-modules-extra-netfilter · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-modules-extra-netfilter · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-modules-usb · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-modules-usb · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-modules-wireless · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-modules-wireless · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-tools · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek-tools · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek64k · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek64k · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek64k-core · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek64k-core · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek64k-devel · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek64k-devel · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek64k-modules · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek64k-modules · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek64k-modules-core · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek64k-modules-core · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek64k-modules-deprecated · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek64k-modules-deprecated · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek64k-modules-desktop · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek64k-modules-desktop · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek64k-modules-extra · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek64k-modules-extra · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek64k-modules-extra-netfilter · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek64k-modules-extra-netfilter · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek64k-modules-usb · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek64k-modules-usb · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek64k-modules-wireless · ol 10 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
kernel-uek64k-modules-wireless · ol 9 0:6.12.0-101.33.4.3.el9uek ELSA-2025-20480 Jul 17, 2025
linux · Debian 13.5 (trixie) 6.12.20-1 DEBIAN-CVE-2025-21958 Apr 1, 2025
linux · Debian 14 6.12.20-1 DEBIAN-CVE-2025-21958 Apr 1, 2025

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