CVE-2025-54879 Mastodon e‑mail throttle misconfiguration allows unlimited email confirmations against unconfirmed emails

Mastodon is a free, open-source social network server based on ActivityPub Mastodon which facilitates LDAP configuration for authentication. In versions 3.1.5 through 4.2.24, 4.3.0 through 4.3.11 and 4.4.0 through 4.4.3, Mastodon's rate-limiting system has a critical configuration error where the...

CVE-2025-54879

CVE-2025-54879 affects Mastodon when using the email-based confirmation throttle. The root cause is a misconfiguration in Mastodon’s rate-limiting: the email throttle checks the password-reset path instead of the confirmation path, effectively disabling per-email limits for confirmation requests....