DDoS Attacks Cause Major Threema Outages

Threema experienced multiple large-scale DDoS attacks that rendered its hosted messaging service unavailable for about four hours and caused intermittent outages thereafter; Threema On-Prem customers were unaffected. The company attributed outages initially to a network issue at its colocation provider, later confirmed the DDoS, communicated updates via social media and email, and deployed additional upstream DDoS protection and planned improvements to its status page.