What is CVE-2025-71309?

CVE-2025-71309 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10, classified as a Improper Locking flaw (CWE-667), affecting Linux kernel versions from 6.19 onward and patched in 6.19.4 and 7.0. CVE-2025-71309 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2025-71309?

CVE-2025-71309 has a CVSS score of 5.5 out of 10, rated Medium severity. The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.

Is there a patch available for CVE-2025-71309?

Yes, CVE-2025-71309 has been patched. Fixed versions include 6.19.4 and 7.0. If you are running Linux kernel 6.19 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2025-71309 actively exploited?

CVE-2025-71309 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is Improper Locking (CWE-667)?

The product does not properly acquire or release a lock, which can lead to unexpected behaviour. See MITRE CWE for full details: https://cwe.mitre.org/data/definitions/667.html

CVE-2025-71309

Medium

In the Linux kernel, the following vulnerability has been resolved: fs/ntfs3: fix deadlock in ni_read_folio_cmpr Syzbot reported a task hung in ni_readpage_cmpr (now ni_read_folio_cmpr). This is caused by a lock inversion deadlock involving the inode mutex (ni_lock) and page locks. Scenario: 1. Task A enters ntfs_read_folio() for page X. It acquires ni_lock. 2. Task A calls ni_read_folio_cmpr(), which attempts to lock all pages in the compressed frame (including page Y). 3. Concurrently, Task B (e.g., via readahead) has locked page Y and calls ntfs_read_folio(). 4. Task B waits for ni_lock (held by A). 5. Task A waits for page Y lock (held by B). -> DEADLOCK. The fix is to restructure locking: do not take ni_lock in ntfs_read_folio(). Instead, acquire ni_lock inside ni_read_folio_cmpr() ONLY AFTER all required page locks for the frame have been successfully acquired. This restores the correct lock ordering (Page Lock -> ni_lock) consistent with VFS. [[email protected]: ni_readpage_cmpr was renamed to ni_read_folio_cmpr]

Package Linux Kernel

Published 2026-05-27

Last modified 2026-06-25

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

5.5

out of 10

Medium

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

None

Availability

High

Vector string

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Weakness type

CWE-667

CVE-2025-71309 is a Improper Locking vulnerability

What is Improper Locking?

The product does not properly acquire or release a lock, which can lead to unexpected behaviour. Learn more on MITRE CWE

Affected versions

Linux kernel versions 6.19 and later are affected. Fixed in 6.19.4, 7.0 and their respective stable series.

Affected from

≥ 6.19

Fixed in

✓ 6.19.4 6.19.x ✓ 7.0

References

2 total

Kernel Git
https://git.kernel.org/stable/c/cfe246b318106e1691bd6c9466c739e8559d25c2

Patch
Kernel Git
https://git.kernel.org/stable/c/e37a75bb866c29da954b51d0dd7670406246d9ee

Patch

Details

CVE ID CVE-2025-71309

Severity Medium

CVSS score 5.5 / 10

CVSS version 3.1

Published 2026-05-27

Modified 2026-06-25

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2025-71309?

CVE-2025-71309 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 , classified as an Improper Locking flaw (CWE-667) . It affects Linux kernel versions from 6.19 onward and has been patched in 6.19.4 and 7.0. CVE-2025-71309 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2025-71309?

CVE-2025-71309 has a CVSS score of 5.5 out of 10, rated Medium severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.
Is there a patch available for CVE-2025-71309?

Yes. CVE-2025-71309 has been patched. Fixed versions include 6.19.4 and 7.0. If you are running Linux kernel 6.19 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2025-71309 actively exploited?

No. CVE-2025-71309 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.