Misskey is an open source, decentralized social media platform. In versions prior to 13.3.2 the URL preview function is subject to a cross site scripting vulnerability due to insufficient URL validation. Arbitrary JavaScript is executed when a malicious URL is loaded in the `View in Player` or `View in Window` preview. This has been fixed in version 13.3.2. Users are advised to upgrade. Users unable to upgrade should avoid usage of the `View in Player` or `View in Window` functions.
Misskey is an open source, decentralized social media platform. In versions prior to 13.3.3 SQL injection is possible due to insufficient parameter validation in the note search API by tag (notes/search-by-tag). This has been fixed in version 13.3.3. Users are advised to upgrade. Users unable to upgrade should block access to the `api/notes/search-by-tag` endpoint.
Misskey is an open source, decentralized social media platform. In versions prior to 13.5.0 the link to the instance to the sender that appears when viewing a user or note received through ActivityPub is not properly validated, so by inserting a URL with a javascript scheme an attacker may execute JavaScript code in the context of the recipient. This issue has been fixed in version 13.5.0. Users are advised to upgrade. Users unable to upgrade should not "view on remote" for untrusted instances.