Hacking Team, the infamous group that sold hacking tools to spy agencies around the world, was hacked earlier this week and all its internal documents released online. As a result of those documents, Adobe has issued an alert about a vulnerability in Flash which Hacking Team was using to exploit victims’ computers, The Next Web reports.

The security hole, which could allow attackers to take control of the system, works across Windows, Mac and Linux.

First spotted by Trend Micro researchers, the document described the “most beautiful Flash bug for the last four years” and included a proof-of-concept for exploiting the hole and writing to memory.

An update to fix the problem is expected to be released later on Wednesday, July 8.