What is CVE-2021-47504?

CVE-2021-47504 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10, affecting Linux kernel versions from 5.1 onward and patched in 5.15.8 and 5.16. CVE-2021-47504 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2021-47504?

CVE-2021-47504 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-2021-47504?

Yes, CVE-2021-47504 has been patched. Fixed versions include 5.15.8 and 5.16. If you are running Linux kernel 5.1 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2021-47504 actively exploited?

CVE-2021-47504 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2021-47504

Medium

In the Linux kernel, the following vulnerability has been resolved: io_uring: ensure task_work gets run as part of cancelations If we successfully cancel a work item but that work item needs to be processed through task_work, then we can be sleeping uninterruptibly in io_uring_cancel_generic() and never process it. Hence we don't make forward progress and we end up with an uninterruptible sleep warning. While in there, correct a comment that should be IFF, not IIF.

Package Linux Kernel

Published 2024-05-24

Last modified 2025-09-29

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

Affected versions

Linux kernel versions 5.1 and later are affected. Fixed in 5.15.8, 5.16 and their respective stable series.

Affected from

≥ 5.1

Fixed in

✓ 5.15.8 5.15.x ✓ 5.16

References

2 total

Kernel Git
https://git.kernel.org/stable/c/78a780602075d8b00c98070fa26e389b3b3efa72

Patch
Kernel Git
https://git.kernel.org/stable/c/8e12976c0c19ebc14b60046b1348c516a74c25a2

Patch

Details

CVE ID CVE-2021-47504

Severity Medium

CVSS score 5.5 / 10

CVSS version 3.1

Published 2024-05-24

Modified 2025-09-29

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2021-47504?

CVE-2021-47504 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 . It affects Linux kernel versions from 5.1 onward and has been patched in 5.15.8 and 5.16. CVE-2021-47504 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2021-47504?

CVE-2021-47504 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-2021-47504?

Yes. CVE-2021-47504 has been patched. Fixed versions include 5.15.8 and 5.16. If you are running Linux kernel 5.1 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2021-47504 actively exploited?

No. CVE-2021-47504 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.