2024-08-14 : The lead Matrix dev claims they already knew about these issues, and, in fact, knowingly shipped cryptography code that was vulnerable to side-channel attacks for years. Most Matrix clients that still depended on libolm should treat this blog as public 0day, unless the Matrix security team already notified you about these issues. A quick survey of the various Matrix clients on GitHub says that libolm is still the most widely used cryptography implementation in the Matrix ecosystem (as of this writing):