Privilege escalation in Zoom client for Windows

1) Link following

EUVDB-ID: #VU27546

Risk: Low

CVSSv4.0: 4.4 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2020-11443

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

Exploit availability: No

Description

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

The vulnerability exists due to MSI installer in Zoom follows symbolic links. A local user can place a specially crafted file into a writable location, trick the victim into installing Zoom client into that location and execute arbitrary code on the system with elevated privileges.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Zoom Workplace Desktop App for Windows: 0.9.10042.0911 - 4.6.11 20559.0413

CPE2.3

• cpe:2.3:a:zoom_video_communications:zoom_client_for_windows:0.9.10042.0911:*:*:*:*:*:*:*
• cpe:2.3:a:zoom_video_communications:zoom_client_for_windows:0.9.10894.0925:*:*:*:*:*:*:*
• cpe:2.3:a:zoom_video_communications:zoom_client_for_windows:0.92.12362.1030:*:*:*:*:*:*:*

External links

https://support.zoom.us/hc/en-us/articles/201361953-New-Updates-for-Windows
https://support.zoom.us/hc/en-us/articles/360043036451-Security-CVE-2020-11443

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.

How the attacker can exploit this vulnerability?

The attacker would have to trick the victim to visit a specially crafted website or open a file.

The attacker would have to login to the system and perform certain actions in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

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