SB2026111108 - Race condition in Linux kernel net xen-netback driver

Description

This security bulletin contains information about 1 vulnerability.

1) Race condition (CVE-ID: CVE-2026-99286)

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

CVSSv4: 5.7 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

The vulnerability allows a local user to potentially cause a denial of service by triggering invalid memory access in the Linux kernel.

The vulnerability exists due to a race condition in Xen netback connection failure cleanup when queue statistics are read concurrently with queue deallocation. A local user can potentially trigger overlapping connection failure cleanup and statistics collection to cause statistics readers to access freed queue memory, potentially crashing the kernel.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/07aca7d25ce8578fedde49855983a01c537a782b
• https://git.kernel.org/stable/c/a97aa838903d15f865d80809f5198ff459c6634a
• https://git.kernel.org/stable/c/ade3082dcdee17c5767069883936d64ff83f6c9f