PT-2026-1244 · Linux+3 · Linux Kernel+3

Published 2026-01-05 · Updated 2026-05-11 · CVE-2025-68756

Positive Technologies (AI Summary)

CVSS v2.0

4.6

Medium

Base vector

AV:L/AC:L/Au:S/C:N/I:N/A:C

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description The Linux kernel contains a flaw related to tagset management within the block layer. Specifically, the blk mq [un]quiesce tagset() functions, used for managing queues, were updated to use quiescing instead of individual queue quiescing, leading to a potential deadlock situation. This deadlock occurs when a thread attempts to quiesce a tagset while another thread is waiting to freeze a queue within that tagset, both contending for the set->tag list lock. The issue arises from the interaction between nvme timeout() and queue freezing operations. The problem is resolved by replacing the mutex lock with Read-Copy-Update (RCU) for safer queue management and list operations.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Exploit

Weakness Enumeration

CWE-833

Related Identifiers

AZL-73421

BDU:2026-00895

CVE-2025-68756

OESA-2026-1759

OESA-2026-1760

OESA-2026-1761

OPENSUSE-SU-2026:10039-1

OPENSUSE-SU-2026:10301-1

USN-8094-1

USN-8094-2

USN-8094-3

USN-8094-4

USN-8094-5

USN-8152-1

USN-8179-1

USN-8179-2

USN-8179-3

USN-8179-4

USN-8184-1

USN-8185-1

USN-8185-2

USN-8203-1

USN-8204-1

USN-8258-1

USN-8260-1

USN-8261-1

USN-8265-1

Affected Products

Debian

Linuxmint

Linux Kernel

Ubuntu

References · 1070

• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/68xxx/CVE-2025-68756.json · Exploit
• https://ubuntu.com/security/CVE-2025-71095 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-23139 · Security Note
• https://ubuntu.com/security/CVE-2025-68340 · Vendor Advisory
• https://ubuntu.com/security/CVE-2025-68244 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-23136 · Security Note
• https://ubuntu.com/security/CVE-2025-40321 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-23137 · Security Note
• https://osv.dev/vulnerability/USN-8203-1 · Vendor Advisory
• https://ubuntu.com/security/CVE-2025-40051 · Vendor Advisory
• https://ubuntu.com/security/CVE-2025-68307 · Vendor Advisory
• https://ubuntu.com/security/CVE-2025-68758 · Vendor Advisory
• https://ubuntu.com/security/CVE-2025-68337 · Vendor Advisory
• https://ubuntu.com/security/CVE-2025-68818 · Vendor Advisory
• https://ubuntu.com/security/CVE-2025-40315 · Vendor Advisory