Race condition in Gentoo Portage

Published: 2020-01-21 | Updated: 2020-05-25

Risk	Low
Patch available	YES
Number of vulnerabilities	1
CVE-ID	CVE-2019-20384
CWE-ID	CWE-362
Exploitation vector	Local
Public exploit	N/A
Vulnerable software Subscribe	Portage Other software / Other software solutions
Vendor	Gentoo

Security Bulletin

This security bulletin contains information about 1 vulnerabilities.

Updated: 29.01.2020

Updated list of vulnerable versions.

Updated: 02.02.2020

Added version 2.3.87 to the list of affected versions.

Updated: 25.05.2020

Changed bulletin status to patched.

1) Race condition

EUVDB-ID: #VU24452

Risk: Low

CVSSv3.1: 6.4 [CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:U/RC:C]

CVE-ID: CVE-2019-20384

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 escalate privileges on the system.

The vulnerability exists due to a race condition. A local user can place a Trojan horse plugin in the "/usr/lib64/nagios/plugins" directory by leveraging access to the nagios user account, because this directory is writable in between a call to emake and a call to fowners.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Portage: 2.3.0 - 2.3.99

External links

http://bugs.gentoo.org/692492
http://gitweb.gentoo.org/repo/gentoo.git/commit/?id=7f03ec4a46055a75eb13bf5fad85cf451822f589

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.