CVE-2026-23393

HIGH EPSS 1.0%
Published Mar 25, 20263mo ago · Modified Jun 17, 20261w ago
7.8 CVSS 3.1
High
Find Similar
Published Mar 25, 2026 3mo ago
Last Modified Jun 17, 2026 1w ago

Description

In the Linux kernel, the following vulnerability has been resolved: bridge: cfm: Fix race condition in peer_mep deletion When a peer MEP is being deleted, cancel_delayed_work_sync() is called on ccm_rx_dwork before freeing. However, br_cfm_frame_rx() runs in softirq context under rcu_read_lock (without RTNL) and can re-schedule ccm_rx_dwork via ccm_rx_timer_start() between cancel_delayed_work_sync() returning and kfree_rcu() being called. The following is a simple race scenario: cpu0 cpu1 mep_delete_implementation() cancel_delayed_work_sync(ccm_rx_dwork); br_cfm_frame_rx() // peer_mep still in hlist if (peer_mep->ccm_defect) ccm_rx_timer_start() queue_delayed_work(ccm_rx_dwork) hlist_del_rcu(&peer_mep->head); kfree_rcu(peer_mep, rcu); ccm_rx_work_expired() // on freed peer_mep To prevent this, cancel_delayed_work_sync() is replaced with disable_delayed_work_sync() in both peer MEP deletion paths, so that subsequent queue_delayed_work() calls from br_cfm_frame_rx() are silently rejected. The cc_peer_disable() helper retains cancel_delayed_work_sync() because it is also used for the CC enable/disable toggle path where the work must remain re-schedulable.

CVSS Details

Base Score
7.8
Exploitability
1.8
Impact
5.9
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack Vector Local
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality High
Integrity High
Availability High

Threat Intelligence

EPSS Exploit Probability
1.0% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 1

CWE-362

Affected Products 11

VendorProductVersionRange
linuxlinux_kernel*≥5.11.1  –  <6.12.78
linuxlinux_kernel*≥6.13  –  <6.18.20
linuxlinux_kernel*≥6.19  –  <6.19.10
linuxlinux_kernel5.11any
linuxlinux_kernel7.0any
linuxlinux_kernel7.0any
linuxlinux_kernel7.0any
linuxlinux_kernel7.0any
linuxlinux_kernel7.0any
linuxlinux_kernel7.0any
linuxlinux_kernel7.0any

References 4

  • git.kernel.org https://git.kernel.org/stable/c/1fd81151f65927fd9edb8ecd12ad45527dbbe5ab
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/3715a00855316066cdda69d43648336367422127
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/d8f35767bacb3c7769d470a41cf161e3f3c07e70
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/e89dbd2736a45f0507949af4748cbbf3ff793146
    Patch

Remediation

  • git.kernel.org https://git.kernel.org/stable/c/1fd81151f65927fd9edb8ecd12ad45527dbbe5ab
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/3715a00855316066cdda69d43648336367422127
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/d8f35767bacb3c7769d470a41cf161e3f3c07e70
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/e89dbd2736a45f0507949af4748cbbf3ff793146
    Patch