CVE-2026-23465

/// Technical description

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

btrfs: log new dentries when logging parent dir of a conflicting inode

If we log the parent directory of a conflicting inode, we are not logging

the new dentries of the directory, so when we finish we have the parent

directory's inode marked as logged but we did not log its new dentries.

As a consequence if the parent directory is explicitly fsynced later and

it does not have any new changes since we logged it, the fsync is a no-op

and after a power failure the new dentries are missing.

Example scenario:

$ mkdir foo

$ sync

$rmdir foo

$ mkdir dir1

$ mkdir dir2

# A file with the same name and parent as the directory we just deleted

# and was persisted in a past transaction. So the deleted directory's

# inode is a conflicting inode of this new file's inode.

$ touch foo

$ ln foo dir2/link

# The fsync on dir2 will log the parent directory (".") because the

# conflicting inode (deleted direc

/// 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