We've released an important security patch for the 3.0.9a version (public branch) just now. Server owners are encouraged to update their servers as soon as possible.
- Fixed a spectate command exploit that caused servers to hang.
This update will be applied automatically very shortly or upon restarting your Steam client. We'll always try to patch any exploit that pops up to the main public version. Meanwhile, our focus is to continue working on the next major update, which you can check our latest news for information regarding it.
- Zombie Panic! Team