CVE-2026-22246

Mastodon is a free, open-source social network server based on ActivityPub. Mastodon 4.3 added notifications of severed relationships, allowing end-users to inspect the relationships they lost as the result of a moderation action. The code allowing users to download lists of severed relationships...

CVE-2026-22246 Local Mastodon users can enumerate and access severed relationships of every other local user

Mastodon is a free, open-source social network server based on ActivityPub. Mastodon 4.3 added notifications of severed relationships, allowing end-users to inspect the relationships they lost as the result of a moderation action. The code allowing users to download lists of severed relationships...

PT-2026-2182

Name of the Vulnerable Software and Affected Versions Mastodon versions 4.3 through 4.3.16 Mastodon versions 4.4 through 4.4.10 Mastodon versions 4.5 through 4.5.3 Description Mastodon is a free, open-source social network server based on ActivityPub. A flaw exists in the code handling the downlo...