Decades-Old Squid Proxy Flaw ‘Squidbleed’ Can Expose User Data

Squidbleed is a memory leak vulnerability (a flaw where a program accidentally exposes data stored in computer memory) in Squid Proxy, a widely used caching tool that has existed since 1997. An attacker controlling an FTP server could trick Squid into reading beyond its allocated memory space and expose HTTP request data from other users on the same proxy, potentially revealing passwords and authentication tokens, especially in shared network environments like schools or offices. The vulnerability primarily affects unencrypted HTTP traffic and poses the biggest risk where multiple users share a single Squid instance.