Linux Kernel up to 5.10.87/5.15.10 hns3_remove use after free

Summaryinfo

A vulnerability identified as critical has been detected in Linux Kernel up to 5.10.87/5.15.10. The impacted element is the function hns3_remove. This manipulation causes use after free. The identification of this vulnerability is CVE-2021-47596. There is no exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 5.10.87/5.15.10. It has been declared as critical. Affected by this vulnerability is the function hns3_remove. The manipulation with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: net: hns3: fix use-after-free bug in hclgevf_send_mbx_msg Currently, the hns3_remove function firstly uninstall client instance, and then uninstall acceletion engine device. The netdevice is freed in client instance uninstall process, but acceletion engine device uninstall process still use it to trace runtime information. This causes a use after free problem. So fixes it by check the instance register state to avoid use after free.

The advisory is shared at git.kernel.org. This vulnerability is known as CVE-2021-47596 since 05/24/2024. The exploitation appears to be easy. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 10/04/2025).

Upgrading to version 5.10.88 or 5.15.11 eliminates this vulnerability. Applying the patch 12512bc8f25b/4f4a353f6fe0/27cbf64a766e is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2024-1418). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• IBM InfoSphere Guardium
• Oracle Linux
• Oracle VM
• IBM Security Guardium
• RESF Rocky Linux
• Broadcom Brocade SANnav
• Dell NetWorker
• Open Source Linux Kernel
• IBM QRadar SIEM
• Dell Avamar
• IBM Storage Scale
• Juniper Junos Space
• SolarWinds Security Event Manager
• Dell PowerProtect Data Domain

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 5.10.0
• 5.10.1
• 5.10.2
• 5.10.3
• 5.10.4
• 5.10.5
• 5.10.6
• 5.10.7
• 5.10.8
• 5.10.9
• 5.10.10
• 5.10.11
• 5.10.12
• 5.10.13
• 5.10.14
• 5.10.15
• 5.10.16
• 5.10.17
• 5.10.18
• 5.10.19
• 5.10.20
• 5.10.21
• 5.10.22
• 5.10.23
• 5.10.24
• 5.10.25
• 5.10.26
• 5.10.27
• 5.10.28
• 5.10.29
• 5.10.30
• 5.10.31
• 5.10.32
• 5.10.33
• 5.10.34
• 5.10.35
• 5.10.36
• 5.10.37
• 5.10.38
• 5.10.39
• 5.10.40
• 5.10.41
• 5.10.42
• 5.10.43
• 5.10.44
• 5.10.45
• 5.10.46
• 5.10.47
• 5.10.48
• 5.10.49
• 5.10.50
• 5.10.51
• 5.10.52
• 5.10.53
• 5.10.54
• 5.10.55
• 5.10.56
• 5.10.57
• 5.10.58
• 5.10.59
• 5.10.60
• 5.10.61
• 5.10.62
• 5.10.63
• 5.10.64
• 5.10.65
• 5.10.66
• 5.10.67
• 5.10.68
• 5.10.69
• 5.10.70
• 5.10.71
• 5.10.72
• 5.10.73
• 5.10.74
• 5.10.75
• 5.10.76
• 5.10.77
• 5.10.78
• 5.10.79
• 5.10.80
• 5.10.81
• 5.10.82
• 5.10.83
• 5.10.84
• 5.10.85
• 5.10.86
• 5.10.87
• 5.15.0
• 5.15.1
• 5.15.2
• 5.15.3
• 5.15.4
• 5.15.5
• 5.15.6
• 5.15.7
• 5.15.8
• 5.15.9
• 5.15.10

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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CVSSv4info

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Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

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Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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