#VU90956 Improper error handling in Linux kernel - CVE-2021-47143

Vulnerability identifier: #VU90956

Vulnerability risk: Low

CVSSv4.0: 4.3 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-47143

CWE-ID: CWE-388

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
Linux kernel
Operating systems & Components / Operating system

Vendor: Linux Foundation

Description

The vulnerability allows a local user to perform a denial of service (DoS) attack.

The vulnerability exists due to improper error handling within the EXPORT_SYMBOL_GPL() and smcd_register_dev() functions in net/smc/smc_ism.c. A local user can perform a denial of service (DoS) attack.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: 5.10, 5.10 rc1, 5.10 rc2, 5.10 rc3, 5.10 rc4, 5.10 rc5, 5.10 rc7, 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, 5.12, 5.12 rc1, 5.12 rc2, 5.12 rc3, 5.12 rc4, 5.12 rc6, 5.12 rc8, 5.12.1, 5.12.2, 5.12.3, 5.12.4, 5.12.5, 5.12.6, 5.12.7, 5.12.8, 5.13 rc1, 5.13 rc4, 5.13 rc5

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External links
https://git.kernel.org/stable/c/8b2cdc004d21a7255f219706dca64411108f7897
https://git.kernel.org/stable/c/40588782f1016c655ae1d302892f61d35af96842
https://git.kernel.org/stable/c/444d7be9532dcfda8e0385226c862fd7e986f607
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.10.42
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.12.9
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.13

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.