Security researchers have identified a critical vulnerability in the PHP programming language that has been exploited by ransomware criminals, resulting in the infection of over 1,000 servers primarily located in China. The vulnerability allows attackers to execute malicious code on web servers, encrypting files and demanding a ransom of approximately $6,500 for decryption. Known as TellYouThePass, the ransomware strain leverages a flaw in PHP's Unicode to ASCII conversion process, allowing attackers to bypass security measures and gain access to sensitive data. The exploit, first reported on June 6, has been used to install ransomware on vulnerable systems, targeting servers running in CGI mode or using the XAMPP platform. Security experts urge PHP users on Windows systems to update their software to prevent further attacks, emphasizing the importance of proactive measures to safeguard against cyber threats.