# CVE-2026-22995: linux: In the Linux kernel, the following vulnerability has been resolved:  ublk: fix use-after-free in ublk_partition_scan_...

CVE-2026-22995 is fixed in linux on 1 platform by DEBIAN-CVE-2026-22995 (version 6.18.8-1), released January 23, 2026. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2026-22995
- Priority: High
- CVSS: 7.8 (high)
- EPSS: 0.0013
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jan 23, 2026

## Description

In the Linux kernel, the following vulnerability has been resolved:  ublk: fix use-after-free in ublk_partition_scan_work  A race condition exists between the async partition scan work and device teardown that can lead to a use-after-free of ub->ub_disk:  1. ublk_ctrl_start_dev() schedules partition_scan_work after add_disk() 2. ublk_stop_dev() calls ublk_stop_dev_unlocked() which does:    - del_gendisk(ub->ub_disk)    - ublk_detach_disk() sets ub->ub_disk = NULL    - put_disk() which may free the disk 3. The worker ublk_partition_scan_work() then dereferences ub->ub_disk    leading to UAF  Fix this by using ublk_get_disk()/ublk_put_disk() in the worker to hold a reference to the disk during the partition scan. The spinlock in ublk_get_disk() synchronizes with ublk_detach_disk() ensuring the worker either gets a valid reference or sees NULL and exits early.  Also change flush_work() to cancel_work_sync() to avoid running the partition scan work unnecessarily when the disk is already detached.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | linux Debian 14 | 6.18.8-1 | [DEBIAN-CVE-2026-22995](https://patchblox.com/security/data/fix/linux/debian-cve-2026-22995.md) | Jan 23, 2026 |

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Data as of 2026-11-08T06:59:42Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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