SB2026102219 - Race condition in Linux kernel smb client

Description

This security bulletin contains information about 1 vulnerability.

1) Race condition (CVE-ID: CVE-2026-98449)

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

CVSSv4: 2 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]

The vulnerability allows a local user to cause incorrect SMB credit accounting, potentially disrupting SMB client operation.

The vulnerability exists due to a race condition in the Linux kernel SMB client's compound_send_recv() function when handling a compound request send failure during reconnection. A local user can trigger a socket send failure during a compound request to leave pending request entries accessible to reconnect callbacks, causing both the callbacks and the send-error path to return the same credits and decrement the in_flight counter twice.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/70783946f3b5d0c06ec7df0f5e7bec2bfad24efb
• https://git.kernel.org/stable/c/8f6f8a48399f82f4a83f7b9f25b9707e0062a4f9