Proofpoint offices in Toronto, Canada. (Raysonho @ Open Grid Scheduler / Scalable Grid Engine, CC0, via Wikimedia Commons) Researchers issued a warning on Wednesday to any company running cloud apps, reporting that in 2020 they detected more than 180 different malicious open authorization (OAuth) applications attacking 55% of their customers with a success rate of 22%. In a blog post, the Proofpoint researchers said that while OAuth apps add business features and user interface enhancements to major cloud platforms such as Microsoft 365 and Google Workspace, theyâre also a threat because bad actors now use malicious OAuth 2.0 applications â or cloud malware â to siphon data and access sensitive information.