CVE-2026-64141

Technical Description

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

ksmbd: fix null pointer dereference in compare_guid_key()

session_fd_check() walks the per-inode m_op_list during durable-handle

session teardown and sets op->conn = NULL for every opinfo whose conn

matched the closing session's connection. The matching opinfo, however,

stays linked in its per-ClientGuid lease_table_list entry's lb->lease_list

because destroy_lease_table() only runs on full TCP-connection teardown,

not on SESSION_LOGOFF.

If the same TCP connection then negotiates a fresh session with the

same ClientGuid (ClientGuid is bound to NEGOTIATE, not the session, and

is unchanged across LOGOFF + SETUP) and issues a SMB2 CREATE with a

lease context on a different inode, find_same_lease_key() walks

lb->lease_list, reaches the stale opinfo, and calls compare_guid_key(),

which unconditionally dereferences opinfo->conn->ClientGUID. The conn

pointer is NULL and the kernel panics.

Reproducer requires only a succes

Remediation

Check the references section for vendor advisories and patches from linux. Update linux_kernel to the latest patched version. 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.

Affected Products

References