Joinmastodon: >> Mastodon >> 4.2.17 Security Vulnerabilities
Mastodon is a free, open-source social network server based on ActivityPub. In versions before 4.4.6, 4.3.14, and 4.2.27, disabling or suspending a user account does not disconnect the account from the streaming API. This allows disabled or suspended accounts to continue receiving real-time updates through existing streaming connections and to establish new streaming connections, even though they cannot interact with other API endpoints. This undermines moderation actions, as administrators expect disabled or suspended accounts to be fully disconnected from the service. This issue has been patched in versions 4.4.6, 4.3.14, and 4.2.27. No known workarounds exist.
CVSS Score
4.3
EPSS Score
0.001
Published
2025-10-13
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 email-based throttle for confirmation emails incorrectly checks the password reset path instead of the confirmation path, effectively disabling per-email limits for confirmation requests. This allows attackers to bypass rate limits by rotating IP addresses and send unlimited confirmation emails to any email address, as only a weak IP-based throttle (25 requests per 5 minutes) remains active. The vulnerability enables denial-of-service attacks that can overwhelm mail queues and facilitate user harassment through confirmation email spam. This is fixed in versions 4.2.24, 4.3.11 and 4.4.3.
CVSS Score
5.3
EPSS Score
0.001
Published
2025-08-06
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