Denial of service in Linux kernel

1) Race condition

EUVDB-ID: #VU27480

Risk: Low

CVSSv3.1: 4.8 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2020-12114

CWE-ID: CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

Exploit availability: No

Description

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

The vulnerability exists due to a race condition between threads updating mountpoint reference counter. A local user can exploit the race and crash the system.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Linux kernel: 4.4 - 4.19.118

External links

http://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.9.221
http://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.19.119
http://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.4.221
http://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.14.178
http://seclists.org/oss-sec/2020/q2/86

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.