#VU92011 Improper locking in Linux kernel - CVE-2021-47451

Vulnerability identifier: #VU92011

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-2021-47451

CWE-ID: CWE-667

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 locking within the idletimer_tg_create() function in net/netfilter/xt_IDLETIMER.c. A local user can perform a denial of service (DoS) attack.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: All versions

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External links
https://git.kernel.org/stable/c/2a670c323055282c9b72794a491d53cef86bbeaf
https://git.kernel.org/stable/c/cae7cab804c943d723d52724a3aeb07a3f4a2650
https://git.kernel.org/stable/c/902c0b1887522a099aa4e1e6b4b476c2fe5dd13e

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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.