What is CVE-2021-47312?

CVE-2021-47312 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 5.13.2 onward and patched in 5.13.5. CVE-2021-47312 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2021-47312?

CVE-2021-47312 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-2021-47312?

Yes, CVE-2021-47312 has been patched. Fixed versions include 5.13.5. If you are running Linux kernel 5.13.2 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2021-47312 actively exploited?

CVE-2021-47312 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-2021-47312

Medium

In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: Fix dereference of null pointer flow In the case where chain->flags & NFT_CHAIN_HW_OFFLOAD is false then nft_flow_rule_create is not called and flow is NULL. The subsequent error handling execution via label err_destroy_flow_rule will lead to a null pointer dereference on flow when calling nft_flow_rule_destroy. Since the error path to err_destroy_flow_rule has to cater for null and non-null flows, only call nft_flow_rule_destroy if flow is non-null to fix this issue. Addresses-Coverity: ("Explicity null dereference")

Package Linux Kernel

Published 2024-05-21

Last modified 2025-04-02

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-2021-47312 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 5.13.2 and later are affected. Fixed in 5.13.5 and their respective stable series.

Affected from

≥ 5.13.2

Fixed in

✓ 5.13.5 5.13.x

References

2 total

Kernel Git
https://git.kernel.org/stable/c/4ca041f919f13783b0b03894783deee00dbca19a

Patch
Kernel Git
https://git.kernel.org/stable/c/70a5a1950cca02c5cd161bb3846b4d983eed97d3

Patch

Details

CVE ID CVE-2021-47312

Severity Medium

CVSS score 5.5 / 10

CVSS version 3.1

Published 2024-05-21

Modified 2025-04-02

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2021-47312?

CVE-2021-47312 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 5.13.2 onward and has been patched in 5.13.5. CVE-2021-47312 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2021-47312?

CVE-2021-47312 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-2021-47312?

Yes. CVE-2021-47312 has been patched. Fixed versions include 5.13.5. If you are running Linux kernel 5.13.2 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2021-47312 actively exploited?

No. CVE-2021-47312 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.