Vulnerability identifier: #VU51949

Vulnerability risk: Low

CVSSv3.1: 5.8 [CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2020-25584

CWE-ID: CWE-362

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
FreeBSD
Operating systems & Components / Operating system

Vendor: FreeBSD Foundation

Description

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to a race condition between lookup of ".." and remounting a filesystem. A local administrator can change the root directory outside of the jail and gain full read and write access to all files and directories in the system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

FreeBSD: 11.0 - 12.1

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External links
http://www.freebsd.org/security/advisories/FreeBSD-SA-21:10.jail_mount.asc

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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.