Ubuntu update for chrony

1) Link following

EUVDB-ID: #VU46134

Risk: Medium

CVSSv4.0: 1.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2020-14367

CWE-ID: CWE-59 - Improper Link Resolution Before File Access ('Link Following')

Exploit availability: No

Description

The vulnerability allows a remote attacker to compromise the target system.

The vulnerability exists due to a symlink following issue when creating the PID file under the "/var/run/chrony" folder. A remote authenticated attacker can create a symlink with the default PID file name pointing to any destination file in the system, resulting in data loss and a denial of service (DoS).

Mitigation

Update the affected package chrony to the latest version.

Vulnerable software versions

Ubuntu: 18.04 - 20.04

chrony (Ubuntu package): before 3.2-4ubuntu4.5

CPE2.3

• cpe:2.3:o:canonical:ubuntu:18.04:*:*:*:*:*:*:*
• cpe:2.3:o:canonical:ubuntu:20.04:*:*:*:*:*:*:*
• cpe:2.3:a:canonical:chrony_ubuntu_package:*:*:*:*:*:ubuntu:*:*

External links

https://ubuntu.com/security/notices/USN-4475-1

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.