CVE-2025-38527

/// Technical description

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

smb: client: fix use-after-free in cifs_oplock_break

A race condition can occur in cifs_oplock_break() leading to a

use-after-free of the cinode structure when unmounting:

cifs_oplock_break()

_cifsFileInfo_put(cfile)

cifsFileInfo_put_final()

cifs_sb_deactive()

[last ref, start releasing sb]

kill_sb()

kill_anon_super()

generic_shutdown_super()

evict_inodes()

dispose_list()

evict()

destroy_inode()

call_rcu(&inode->i_rcu, i_callback)

spin_lock(&cinode->open_file_lock) <- OK

[later] i_callback()

cifs_free_inode()

kmem_cache_free(cinode)

spin_unlock(&cinode->open_file_lock) <- UAF

cifs_done_oplock_break(cinode) <- UAF

The issue occur

/// 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