Misskey is an open source, federated social media platform. Starting in version 12.31.0 and prior to version 2025.4.1, missing validation in Mk:api
allows malicious AiScript code to access additional endpoints that it isn't designed to have access to. The missing validation allows malicious AiScript code to prefix a URL with ../
to step out of the /api
directory, thereby being able to make requests to other endpoints, such as /files
, /url
, and /proxy
. Version 2025.4.1 fixes the issue.