CVE-2025-71070

A reference count leak flaw was found in the Linux kernel's ublk (userspace block driver) subsystem. When a ublk server process exits while requests are still pending, the reference counts for those requests are not properly decremented. This leads to WARN_ON_ONCE warnings and could potentially allow stale operations on completed requests.

The ublk subsystem is a relatively new feature for userspace block device implementations. This bug triggers kernel warnings rather than crashes, and exploitation would require a malicious or buggy ublk server application. Systems not using ublk devices are completely unaffected.

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.