Remote code execution in Zoom Chat for Windows

1) Input validation error

EUVDB-ID: #VU52199

Risk: High

CVSSv4.0: 5.7 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2021-30480

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

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

The vulnerability exists due to insufficient validation of user-supplied input, related to contact requests in Zoom Chat feature. A remote Zoom user can pass specially crafted request to the application and execute arbitrary code on the system.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Zoom Workplace Desktop App for Windows: 5.0.0 23168.0427 - 5.6.1 617

CPE2.3

• cpe:2.3:a:zoom_video_communications:zoom_client_for_windows:5.0.0:23168.0427:*:*:*:*:*:*
• cpe:2.3:a:zoom_video_communications:zoom_client_for_windows:5.0.1:23502.0430:*:*:*:*:*:*
• cpe:2.3:a:zoom_video_communications:zoom_client_for_windows:5.0.3:24951.0515:*:*:*:*:*:*

External links

https://blog.malwarebytes.com/exploits-and-vulnerabilities/2021/04/zoom-zero-day-discovery-makes-calls-safer-hackers-200000-richer/
https://twitter.com/thezdi/status/1379855435730149378
https://twitter.com/thezdi/status/1379859851061395459
https://www.securityweek.com/200000-awarded-zero-click-zoom-exploit-pwn2own
https://www.zdnet.com/article/critical-zoom-vulnerability-triggers-remote-code-execution-without-user-input/
https://zoom.us/feature/messaging

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

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.

Is there known malware, which exploits this vulnerability?

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