A remote attacker who has not logged in can crash many HTTP/3 web servers with a single connection, security firm FoxIO disclosed, releasing working proof-of-concept code.

By sending a small batch of compressed HTTP headers that expands in memory to a much larger set, the attacker can force the server to use thousands of times more memory than it received, enough to run a default server



Source: TheHackerNews
Source Link: https://thehackernews.com/2026/10/new-qpack-flaws-can-crash-http3-servers.html