Paaster is a pastebin application. Prior to version 3.3.0, Paaster's account login has no rate limiting, lockout, or CAPTCHA of any kind, and a companion endpoint openly discloses whether a username exists along with that account's password-hashing salts. Together these let an attacker enumerate real accounts and then brute-force their passwords with unlimited, unthrottled attempts. This issue has been patched in version 3.3.0.
CWE-204, CWE-307