Summary On September 24, 2019, Percona’s IT and IT Security teams were made aware of a denial of service attack on www.percona.com/forums. We use vBulletin to host Percona Forums, which was subjected to a zero-day pre-authentication remote code execution. This vulnerability potentially allows an unauthenticated attacker to remotely execute code on, or possibly complete control [&]

https://www.percona.com/blog/2019/09/25/incident-involving-percona-forums-on-september-24-2019/