Cloudflare's Signal & Discord Leak Vulnerability | Simplified Privacy

A 15-year-old hacker showed that Cloudflare's caching can be abused to identify which Cloudflare server a Signal or Discord user downloads images from, which can reveal an approximate city or VPN exit location. The attack only requires sending the victim an image, and the hacker used Cloudflare WARP to access cached data and Burp to control what was sent to Signal's CDN servers. Cloudflare made the attack harder after the disclosure but had not fully patched it at the time of writing. Any VPN can block this specific attack, according to the text, which also raises concerns about the centralization of large providers.