What is CVE-2025-21863?

CVE-2025-21863 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10, affecting Linux kernel versions from 5.6 onward and patched in 5.15.209, 6.1.175, 6.6.80 and others. CVE-2025-21863 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2025-21863?

CVE-2025-21863 has a CVSS score of 7.8 out of 10, rated High severity. The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Is there a patch available for CVE-2025-21863?

Yes, CVE-2025-21863 has been patched. Fixed versions include 5.15.209, 6.1.175, 6.6.80 and others. If you are running Linux kernel 5.6 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2025-21863 actively exploited?

CVE-2025-21863 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2025-21863

High

In the Linux kernel, the following vulnerability has been resolved: io_uring: prevent opcode speculation sqe->opcode is used for different tables, make sure we santitise it against speculations.

Package Linux Kernel

Published 2025-03-12

Last modified 2026-06-01

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

7.8

out of 10

High

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Vector string

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

Affected versions

Linux kernel versions 5.6 and later are affected. Fixed in 5.15.209, 6.1.175, 6.6.80, 6.12.17, 6.13.5, 6.14 and their respective stable series.

Affected from

≥ 5.6

Fixed in

✓ 5.15.209 5.15.x ✓ 6.1.175 6.1.x ✓ 6.6.80 6.6.x ✓ 6.12.17 6.12.x ✓ 6.13.5 6.13.x ✓ 6.14

References

The following references provide additional information about CVE-2025-21863 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.

Kernel patch commit
https://git.kernel.org/stable/c/18eae8420081ef8e043ad455937bfb470ef08607
Patch
Kernel patch commit
https://git.kernel.org/stable/c/1e988c3fe1264708f4f92109203ac5b1d65de50b
Patch
Kernel patch commit
https://git.kernel.org/stable/c/506b9b5e8c2d2a411ea8fe361333f5081c56d23a
Patch

6 patch commits total View all on NVD

Details

CVE ID CVE-2025-21863

Severity High

CVSS score 7.8 / 10

CVSS version 3.1

Published 2025-03-12

Modified 2026-06-01

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2025-21863?

CVE-2025-21863 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10 . It affects Linux kernel versions from 5.6 onward and has been patched in 5.15.209, 6.1.175, 6.6.80 and others. CVE-2025-21863 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2025-21863?

CVE-2025-21863 has a CVSS score of 7.8 out of 10, rated High severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
Is there a patch available for CVE-2025-21863?

Yes — CVE-2025-21863 has been patched. Fixed versions include 5.15.209, 6.1.175, 6.6.80 and others. If you are running Linux kernel 5.6 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2025-21863 actively exploited?

No — CVE-2025-21863 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.