SB2026082493 - Race condition in Linux kernel bpf

Description

This security bulletin contains information about 1 vulnerability.

1) Race condition (CVE-ID: CVE-2026-74686)

CWE-ID: CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

CVSSv4: 6.8 [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]

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to improper synchronization in rqspinlock slowpath handling in kernel/bpf/rqspinlock.c when processing ABBA deadlock conditions in the waiter queue. A local user can trigger a deadlock scenario that leaves the final waiter blocked to cause a denial of service.

The issue can lead to intermittent stalls and, if no subsequent waiter joins the queue, may stall indefinitely.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/7a3c0289c3c8eb4607dff448ae9ff9f902c813af
• https://git.kernel.org/stable/c/f54667b0c16213285c9d9b8e3929f738b8f71826