Mastodon is a free, open-source social network server based on ActivityPub. Starting in version 4.2.0-beta1 and prior to version 4.2.0-rc2, by crafting specific input, attackers can inject arbitrary data into HTTP requests issued by Mastodon. This can be used to perform confused deputy attacks if the server configuration includes ALLOWED_PRIVATE_ADDRESSES
to allow access to local exploitable services. Version 4.2.0-rc2 has a patch for the issue.
{ "cpes": [ "cpe:2.3:a:joinmastodon:mastodon:4.2.0:beta1:*:*:*:*:*:*", "cpe:2.3:a:joinmastodon:mastodon:4.2.0:beta2:*:*:*:*:*:*", "cpe:2.3:a:joinmastodon:mastodon:4.2.0:beta3:*:*:*:*:*:*", "cpe:2.3:a:joinmastodon:mastodon:4.2.0:rc1:*:*:*:*:*:*" ], "severity": "Medium" }