CVE-2026-43359

A flaw was found in the Linux kernel's Btrfs file system. A local malicious user, who owns a subvolume, can exploit an item overflow vulnerability when repeatedly calling the set received ioctl with the same received UUID field for multiple subvolumes. This can trigger a transaction abort, leading to the file system being mounted in read-only mode, effectively causing a Denial of Service (DoS).

Red Hat acknowledges the upstream Linux kernel correction for «btrfs» as described in COMMENT_ZERO. Fixes are delivered through standard kernel errata for supported products. Operational exposure depends on whether this subsystem or driver is active in your configuration.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

To mitigate this issue, prevent the btrfs module from being loaded. See https://access.redhat.com/solutions/41278 for instructions.