An international law enforcement initiative has dismantled AVCheck, a service that allowed cybercriminals to test malware against antivirus software. The official website, avcheck.net, now displays a seizure banner from U.S. and Dutch authorities. AVCheck was one of the largest counter antivirus services, providing insights into malware evasion tactics. Investigators found connections between AVCheck's administrators and crypting services, which help obfuscate malware. Law enforcement created a deceptive login page to warn users of legal consequences. The takedown occurred on May 27, 2025, as part of Operation Endgame, which also seized 300 servers and 650 domains linked to ransomware attacks.