#VU91465 Race condition in Linux kernel - CVE-2021-47493

Vulnerability identifier: #VU91465

Vulnerability risk: Low

CVSSv4.0: 5.9 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-47493

CWE-ID: CWE-362

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 escalate privileges on the system.

The vulnerability exists due to a race condition within the ocfs2_test_bg_bit_allocatable() function in fs/ocfs2/suballoc.c. A local user can escalate privileges on the system.

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/5043fbd294f5909a080ade0f04b70a4da9e122b7
https://git.kernel.org/stable/c/2e382600e8856ea654677b5134ee66e03ea72bc2
https://git.kernel.org/stable/c/6f1b228529ae49b0f85ab89bcdb6c365df401558

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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.