A leak site is a website operated by cybercriminals, often linked to ransomware groups, where stolen data from breached organizations is published or threatened to be published. These sites are used as part of extortion tactics, pressuring victims to pay a ransom to prevent sensitive information - such as personal, financial, or proprietary business data - from being exposed to the public or sold on the dark web. Leak sites are typically hosted on the dark web to evade law enforcement and are a key component of double extortion schemes in modern cyberattacks.