Threats Tagged 'cve-2025-39730'

Multiple security vulnerabilities have been identified and fixed in the Linux kernel packages used by Red Hat Enterprise Linux 10 and related distributions. These include race conditions, buffer overflows, and improper bounds checking in various kernel subsystems such as NFS, vsock/virtio, memory management, ALSA audio, and WiFi. The update addresses these issues to improve system security and stability. A system reboot is required after applying the update for changes to take effect.

The kernel packages contain the Linux kernel, the core of any Linux operating system. Security Fix(es): * kernel: smb: client: fix use-after-free in cifs_oplock_break (CVE-2025-38527) * kernel: NFS: Fix filehandle bounds checking in nfs_fh_to_dentry() (CVE-2025-39730) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

In the Linux kernel, the following vulnerability has been resolved: NFS: Fix filehandle bounds checking in nfs_fh_to_dentry() The function needs to check the minimal filehandle length before it can access the embedded filehandle.

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 occurs when umount has already released its reference to the superblock. When _cifsFileInfo_put() calls cifs_sb_deactive(), this releases the last reference, triggering the immediate cleanup of all inodes under RCU. However, cifs_oplock_break() continues to access the cinode after this point, resulting in use-after-free. Fix this by holding an extra reference to the superblock during the entire oplock break operation. This ensures that the superblock and its inodes remain valid until the oplock break completes.