Last year we won Pwn2Own by demonstrating remote code execution, using a chain of three vulnerabilities, on the then latest version of the Zoom client. In this talk we would like to share all details of the vulnerabilities we found and how we combined them into a fully working exploit.
When the pandemic required everyone to work from home, we saw a huge growth on the video conferencing market. It was this movement that made the organisation behind the world famous Pwn2Own competition decide to add an 'Enterprise Communications' category to last year’s competition. Everyone who was able to successfully demonstrate a zero-day attack against Zoom or Microsoft Teams would be rewarded $200,000. We decided to take them up on this challenge and started researching Zoom. This resulted in a working remote exploit against the at the time latest version of Zoom that would give the attacker full control over the victim’s system (CVE-2021-34407).
During this talk, we will walk you through how we started our research, explain the vulnerabilities that were found and finally how those vulnerabilities were incorporated into the exploit that successfully performed the attack during the contest.