CVE-2026-64016

Technical Description

In the Linux kernel, the following vulnerability has been resolved:

ksmbd: fix durable reconnect error path file lifetime

After a durable reconnect succeeds, ksmbd_reopen_durable_fd() republishes

the same ksmbd_file into the session volatile-id table. If smb2_open()

then takes a later error path, cleanup first calls ksmbd_fd_put(work, fp)

and then unconditionally calls ksmbd_put_durable_fd(dh_info.fp).

In this case fp and dh_info.fp are the same object. The first put drops the

reconnect lookup reference, but the final durable put can run

__ksmbd_close_fd(NULL, fp). Because the final close is not session-aware,

it can free the file object without removing the volatile-id entry that was

just published into the session table.

Use the session-aware put for the final reconnect drop when the reconnect

had already succeeded and the error path is cleaning up the republished

file. Earlier reconnect failures, before fp is assigned to dh_info.fp, keep

using the durable-only put path.

Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

References