CVE-2021-47312

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")

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/4ca041f919f13783b0b03894783deee00dbca19a	Patch
https://git.kernel.org/stable/c/70a5a1950cca02c5cd161bb3846b4d983eed97d3	Patch
https://git.kernel.org/stable/c/4ca041f919f13783b0b03894783deee00dbca19a	Patch
https://git.kernel.org/stable/c/70a5a1950cca02c5cd161bb3846b4d983eed97d3	Patch

Configurations

Configuration 1 (hide)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

History

02 Apr 2025, 14:40

Type	Values Removed	Values Added
References	~~() https://git.kernel.org/stable/c/4ca041f919f13783b0b03894783deee00dbca19a -~~	() https://git.kernel.org/stable/c/4ca041f919f13783b0b03894783deee00dbca19a - Patch
References	~~() https://git.kernel.org/stable/c/70a5a1950cca02c5cd161bb3846b4d983eed97d3 -~~	() https://git.kernel.org/stable/c/70a5a1950cca02c5cd161bb3846b4d983eed97d3 - Patch
CPE		cpe:2.3:o:linux:linux_kernel::::::::
First Time		Linux linux Kernel Linux

Information

Published : 2024-05-21 15:15

Updated : 2025-04-02 14:40

NVD link : CVE-2021-47312

Mitre link : CVE-2021-47312

CVE.ORG link : CVE-2021-47312

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-476

NULL Pointer Dereference

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