CVE-2026-99279
Received
Received - Intake
ksmbd Session Handling Use-After-Free Vulnerability
Vulnerability report for CVE-2026-99279, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-11-07
Last updated on: 2026-11-07
Assigner: kernel.org
Description
Description
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: reclaim ended sessions on logoff and expiration
LOGOFF and previous-session replacement leave sessions Expired with a
zero credential expiry. Ended sessions can retain their memory and
connection slots when no further setup arrives on the owning connection.
Unpublish a logged-off session while the request reference keeps its
response signing and encryption keys alive. Remove its procfs entry
before dropping the table reference so a reader cannot remove its own
entry on the last put. Clear proc_entry after removal to avoid removing
it twice.
Reclaim ended sessions from the global table in the existing expiration
worker before it acquires conn_list_lock. Only select Expired sessions
with zero credential expiry and no references beyond the table
reference. Keep sessions whose Kerberos credentials expired available
for reauthentication.
Unlink the session from its setup connection and all channel
connections, so SMB2 sessions and sessions with only secondary SMB3
channels are covered. The session already holds connection references,
and sessions_table_lock prevents concurrent channel removal. Queue
sessions on a separate disposal list, leaving their hash nodes unhashed,
and remove procfs entries and drop table references outside the locks.
Keep the pending setup check before allocating a new session so
abandoned InProgress sessions can release their slots even at the
connection limit. Retain the timeout and reference checks and dispose of
those sessions outside the locks. Leave ended Expired sessions to the
expiration worker.
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
Currently, no data is known.
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-UNKNOWN |