CVE-2024-25619

/// Technical description

Mastodon is a free, open-source social network server based on ActivityPub. When an OAuth Application is destroyed, the streaming server wasn't being informed that the Access Tokens had also been destroyed, this could have posed security risks to users by allowing an application to continue listening to streaming after the application had been destroyed. Essentially this comes down to the fact that when Doorkeeper sets up the relationship between Applications and Access Tokens, it uses a `dependent: delete_all` configuration, which means the `after_commit` callback setup on `AccessTokenExtension` didn't actually fire, since `delete_all` doesn't trigger ActiveRecord callbacks. To mitigate, we need to add a `before_destroy` callback to `ApplicationExtension` which announces to streaming that all the Application's Access Tokens are being "killed". Impact should be negligible given the affected application had to be owned by the user. None the less this issue has been addressed in versions

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References