CVE-2026-74307

A flaw was found in the Linux kernel's ext4 filesystem. A local attacker can trigger a deadlock by performing an EXT4_IOC_MOVE_EXT ioctl operation with a donor file from a different filesystem during a concurrent freeze operation. This late validation creates a circular lock dependency, leading to a Denial of Service (DoS).

This vulnerability is rated as Moderate severity because it requires local access and results exclusively in a denial of service, with no compromise to data confidentiality or integrity. Exploitation requires an authenticated user to perform specific extent-reallocation operations across differing filesystem boundaries while a concurrent filesystem freeze takes place. Although ext4 is widely deployed in Red Hat Enterprise Linux environments, the specific timing and conditions necessary to trigger the deadlock restrict the overall blast radius to system availability.

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.

Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.