Linux Distros Unpatched Vulnerability : CVE-2026-53062

critical Nessus Plugin ID 322638

Synopsis

The Linux/Unix host has one or more packages installed with a vulnerability that the vendor indicates will not be patched.

Description

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

- dm cache policy smq: fix missing locks in invalidating cache blocks In passthrough mode, the policy invalidate_mapping operation is called simultaneously from multiple workers, thus it should be protected by a lock. Otherwise, we might end up with data races on the allocated blocks counter, or even use-after- free issues with internal data structures when doing concurrent writes. Note that the existing FIXME in smq_invalidate_mapping() doesn't affect passthrough mode since migration tasks don't exist there, but would need attention if supporting fast device shrinking via suspend/resume without target reloading.
Reproduce steps: 1. Create a cache device consisting of 1024 cache entries dmsetup create cmeta --table 0 8192 linear /dev/sdc 0 dmsetup create cdata --table 0 131072 linear /dev/sdc 8192 dmsetup create corig
--table 0 262144 linear /dev/sdc 262144 dd if=/dev/zero of=/dev/mapper/cmeta bs=4k count=1 oflag=direct dmsetup create cache --table 0 262144 cache /dev/mapper/cmeta \ /dev/mapper/cdata /dev/mapper/corig 128 2 metadata2 writethrough smq 0 2. Populate the cache, and record the number of cached blocks fio
--name=populate --filename=/dev/mapper/cache --rw=randwrite --bs=4k \ --size=64m --direct=1 nr_cached=$(dmsetup status cache | awk '{split($7, a, /); print a[1]}') 3. Reload the cache into passthrough mode dmsetup suspend cache dmsetup reload cache --table 0 262144 cache /dev/mapper/cmeta \ /dev/mapper/cdata /dev/mapper/corig 128 2 metadata2 passthrough smq 0 dmsetup resume cache 4. Write to the passthrough cache. By setting multiple jobs with I/O size equal to the cache block size, cache blocks are invalidated concurrently from different workers. fio --filename=/dev/mapper/cache --name=test
--rw=randwrite --bs=64k \ --direct=1 --numjobs=2 --randrepeat=0 --size=64m 5. Check if demoted matches cached block count. These numbers should match but may differ due to the data race. nr_demoted=$(dmsetup status cache | awk '{print $12}') echo $nr_cached, $nr_demoted (CVE-2026-53062)

Note that Nessus relies on the presence of the package as reported by the vendor.

Solution

There is no known solution at this time.

See Also

https://security-tracker.debian.org/tracker/CVE-2026-53062

Plugin Details

Severity: Critical

ID: 322638

File Name: unpatched_CVE_2026_53062.nasl

Version: 1.1

Type: Local

Agent: unix

Family: Misc.

Published: 6/25/2026

Updated: 6/25/2026

Supported Sensors: Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.4

CVSS v2

Risk Factor: High

Base Score: 7.5

Temporal Score: 6.4

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P

CVSS Score Source: CVE-2026-53062

CVSS v3

Risk Factor: Critical

Base Score: 9.8

Temporal Score: 9

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:U/RL:U/RC:C

Vulnerability Information

CPE: cpe:/o:debian:debian_linux:11.0, p-cpe:/a:debian:debian_linux:linux, cpe:/o:debian:debian_linux:12.0

Required KB Items: Host/local_checks_enabled, Host/cpu, global_settings/vendor_unpatched, Host/OS/identifier

Exploit Ease: No known exploits are available

Vulnerability Publication Date: 6/24/2026

Reference Information

CVE: CVE-2026-53062