CVEvulnerability
CVE-2025-21958
4.7 MEDIUM
Official page ↗
- Status
- Modified
- Published
- 2025-04-01
- Last modified
- 2026-07-30
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- CVSS 3.1 (416baaa9-dc9f-4396-8d5f-8c081fb06d67)
- 7.8 HIGH — CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- CVSS 3.1 ([email protected])
- 4.7 MEDIUM — CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
- Weaknesses
- CWE-367
Description
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.
Affected configurations
• linux linux kernel (>= 6.12 < 6.12.20)
• linux linux kernel (>= 6.13 < 6.13.8)
• linux linux kernel 6.14
Related
Weakness · CWE (1)
- CWE-367 Time-of-check Time-of-use (TOCTOU) Race Condition weakness