Time-of-check Time-of-use (TOCTOU) Race Condition in Linux kernel - #VU135567
Published: June 26, 2026
Vulnerability identifier: #VU135567
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: N/A
CWE-ID: CWE-367
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: Linux Foundation
Affected software:
Linux kernel
Linux kernel
Detailed vulnerability description
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to improper state validation in nfqnl_reinject() in net/netfilter/nfnetlink_queue.c when reinjecting queued bridge packets after bridge port membership changes. A local user can remove a bridge port from the bridge while a packet is queued to cause a denial of service.
The queued skb leaves RCU protection, and the advisory notes that rx_handler_data could point to data that is not a net_bridge_port structure at reinjection time.
Remediation
Install security update from vendor's repository.