What is CVE-2021-47421?

CVE-2021-47421 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 5.10 onward and patched in 5.10.241, 5.14.12 and 5.15. CVE-2021-47421 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2021-47421?

CVE-2021-47421 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-2021-47421?

Yes, CVE-2021-47421 has been patched. Fixed versions include 5.10.241, 5.14.12 and 5.15. If you are running Linux kernel 5.10 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2021-47421 actively exploited?

CVE-2021-47421 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-2021-47421

Medium

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: handle the case of pci_channel_io_frozen only in amdgpu_pci_resume In current code, when a PCI error state pci_channel_io_normal is detectd, it will report PCI_ERS_RESULT_CAN_RECOVER status to PCI driver, and PCI driver will continue the execution of PCI resume callback report_resume by pci_walk_bridge, and the callback will go into amdgpu_pci_resume finally, where write lock is releasd unconditionally without acquiring such lock first. In this case, a deadlock will happen when other threads start to acquire the read lock. To fix this, add a member in amdgpu_device strucutre to cache pci_channel_state, and only continue the execution in amdgpu_pci_resume when it's pci_channel_io_frozen.

Package Linux Kernel

Published 2024-05-21

Last modified 2025-11-03

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-2021-47421 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 5.10 and later are affected. Fixed in 5.10.241, 5.14.12, 5.15 and their respective stable series.

Affected from

≥ 5.10

Fixed in

✓ 5.10.241 5.10.x ✓ 5.14.12 5.14.x ✓ 5.15

References

4 total

Kernel Git
https://git.kernel.org/stable/c/248b061689a40f4fed05252ee2c89f87cf26d7d8

Patch
Kernel Git
https://git.kernel.org/stable/c/72e9a1bf9b722628c28092e0c2cd8717edd201dc

Patch
Kernel Git
https://git.kernel.org/stable/c/785cc093b6b5a93cc350421a55f3f1eda6585156

Patch
Debian Security
https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html

Details

CVE ID CVE-2021-47421

Severity Medium

CVSS score 5.5 / 10

CVSS version 3.1

Published 2024-05-21

Modified 2025-11-03

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2021-47421?

CVE-2021-47421 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 5.10 onward and has been patched in 5.10.241, 5.14.12 and 5.15. CVE-2021-47421 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2021-47421?

CVE-2021-47421 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-2021-47421?

Yes. CVE-2021-47421 has been patched. Fixed versions include 5.10.241, 5.14.12 and 5.15. If you are running Linux kernel 5.10 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2021-47421 actively exploited?

No. CVE-2021-47421 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.