Proxy attacks
Proxy attacks are a form of denial of service attack. These attacks involve proxy swarms which are groups of at least two proxies being commanded by at least one attacker. Proxy attacks occur when a proxy swarm is used against OWOT with the goal of shutting down the server. The most damaging proxy attacks involve dozens of proxies and lead to the server slowing down or crashing. In some cases, dozens of proxies can be used to spam the chat to make it inaccessible.
To date, there have been dozens of proxy attacks with multiple possible perpetrators or groups. One event in particular led to the banning of 1,500 TOR exit nodes in one day which rendered OWOT mostly inaccessible to TOR users.