Quick answers
- Is CVE-2026-99276 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-99276 being exploited in the wild.
- How severe is CVE-2026-99276?
- Informational severity, published 7 November 2026.
- Which products and versions are affected?
- Linux Kernel All versions containing d7fd1f98607f (ksmbd: follow SMB2 session expiration semantics).
- Is there a fix for CVE-2026-99276?
- A patch was published on 2026-11-06: Upstream fix applied Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-99276 attacked?
- It is attacked with local access, in an operating system.
- Am I affected by CVE-2026-99276?
- Check whether you run Linux Kernel at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
A deadlock occurs in ksmbd's session expiration worker and connection scavenging logic due to lock ordering: the expiration worker holds conn_list_lock (read) while checking sessions, but session teardown acquires session locks (write) before attempting to acquire conn_list_lock (read). The fix changes the scavenging check to use non-blocking lock acquisition (down_read_trylock) instead of blocking, deferring the check when locks are contended and allowing the periodic worker to retry later.
Affected products
- Linux Linux kernel All versions containing d7fd1f98607f (ksmbd: follow SMB2 session expiration semantics)
Timeline
- 2026-11-07: disclosed
- 2026-11-06: patched: Upstream fix applied