What is CVE-2021-47183?

CVE-2021-47183 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10, classified as a NULL Pointer Dereference flaw (CWE-476), affecting Linux kernel versions from 2.6.38 onward and patched in 5.10.241, 5.15.5 and 5.16. CVE-2021-47183 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2021-47183?

CVE-2021-47183 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-2021-47183?

Yes, CVE-2021-47183 has been patched. Fixed versions include 5.10.241, 5.15.5 and 5.16. If you are running Linux kernel 2.6.38 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2021-47183 actively exploited?

CVE-2021-47183 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is NULL Pointer Dereference (CWE-476)?

The product dereferences a pointer that it expects to be valid but is NULL, typically causing a crash. See MITRE CWE for full details: https://cwe.mitre.org/data/definitions/476.html

CVE-2021-47183

Medium

In the Linux kernel, the following vulnerability has been resolved: scsi: lpfc: Fix link down processing to address NULL pointer dereference If an FC link down transition while PLOGIs are outstanding to fabric well known addresses, outstanding ABTS requests may result in a NULL pointer dereference. Driver unload requests may hang with repeated "2878" log messages. The Link down processing results in ABTS requests for outstanding ELS requests. The Abort WQEs are sent for the ELSs before the driver had set the link state to down. Thus the driver is sending the Abort with the expectation that an ABTS will be sent on the wire. The Abort request is stalled waiting for the link to come up. In some conditions the driver may auto-complete the ELSs thus if the link does come up, the Abort completions may reference an invalid structure. Fix by ensuring that Abort set the flag to avoid link traffic if issued due to conditions where the link failed.

Package Linux Kernel

Published 2024-04-10

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-476

CVE-2021-47183 is a NULL Pointer Dereference vulnerability

What is NULL Pointer Dereference?

The product dereferences a pointer that it expects to be valid but is NULL, typically causing a crash. Learn more on MITRE CWE

Affected versions

Linux kernel versions 2.6.38 and later are affected. Fixed in 5.10.241, 5.15.5, 5.16 and their respective stable series.

Affected from

≥ 2.6.38

Fixed in

✓ 5.10.241 5.10.x ✓ 5.15.5 5.15.x ✓ 5.16

References

4 total

Kernel Git
https://git.kernel.org/stable/c/1854f53ccd88ad4e7568ddfafafffe71f1ceb0a6

Patch
Kernel Git
https://git.kernel.org/stable/c/28de48a7cea495ab48082d9ff4ef63f7cb4e563a

Patch
Kernel Git
https://git.kernel.org/stable/c/04c1af683270e4709a594bb1691b8800b945035a
Debian Security
https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html

Details

CVE ID CVE-2021-47183

Severity Medium

CVSS score 5.5 / 10

CVSS version 3.1

Published 2024-04-10

Modified 2025-11-03

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2021-47183?

CVE-2021-47183 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 , classified as a NULL Pointer Dereference flaw (CWE-476) . It affects Linux kernel versions from 2.6.38 onward and has been patched in 5.10.241, 5.15.5 and 5.16. CVE-2021-47183 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2021-47183?

CVE-2021-47183 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-2021-47183?

Yes. CVE-2021-47183 has been patched. Fixed versions include 5.10.241, 5.15.5 and 5.16. If you are running Linux kernel 2.6.38 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2021-47183 actively exploited?

No. CVE-2021-47183 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.