#VU87739 Deadlock in Linux kernel - CVE-2021-46987

Vulnerability identifier: #VU87739

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-2021-46987

CWE-ID: CWE-833

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 a deadlock when cloning inline extent with low amount of free metadata space in btrfs. A local user can perform a denial of service (DoS) attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Linux kernel: All versions

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External links
https://git.kernel.org/stable/c/d5347827d0b4b2250cbce6eccaa1c81dc78d8651
https://git.kernel.org/stable/c/96157707c0420e3d3edfe046f1cc797fee117ade
https://git.kernel.org/stable/c/f9baa501b4fd6962257853d46ddffbc21f27e344

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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.