A broken access control vulnerability in Ghost Foundation Ghost 5.x allows authenticated Author-role users to delete posts owned by other users. The post model permissible() cascade is missing the branch that handles the combined isAuthor and isDestroy condition, causing the authorization check to fall through and permit the deletion. An attacker with an Author account can delete any post on the platform.

Ghost is a Node.js content management system. From 6.26.0 until 6.54.1, a validation issue allowed some functionality, such as Webmentions, to be abused by an unauthenticated user to make limited HTTP requests to hosts in the Ghost server's internal network. A successful attack would not result in any response data being returned. This vulnerability is fixed in 6.54.1.

Ghost is a Node.js content management system. From 4.9.0 until 6.54.1, an input validation issue allowed any staff user to create a post with content in feature_image_caption that could be used to hijack another staff user's Ghost Admin session, resulting in privilege escalation. This issue is fixed in 6.54.1.

Ghost is a Node.js content management system. From 0.10.0 until 6.54.1, a vulnerability in custom themes allowed a staff user to write files outside of the uploads directory. This could be used to alter the behavior of the installation through custom theme upload path traversal in LocalStorageBase and theme storage name handling. This issue is fixed in version 6.54.1.

Ghost is a Node.js content management system. From 1.20.1 until 6.54.1, an Administrator-level user could remotely overwrite certain files on the filesystem through the database backup filename, leading to integrity and availability issues. The database export endpoint failed to reject path separators in the caller-supplied filename. This issue is fixed in version 6.54.1.

Ghost is a Node.js content management system. Prior to 6.54.1, any staff-level user was able to leak the hashed passwords of other staff users through the Ghost Admin API. An offline password-guessing attack against the hashes could lead to account takeover if successful, but Device Verification should have prevented an attacker from logging in with a recovered password. Depending on the database used, leaked hashes may not have had the correct casing for all characters, increasing the difficulty of a password-guessing attack. This issue is fixed in version 6.54.1.

Ghost is a Node.js content management system. From 4.22.0 until 6.54.1, a missing validation check allowed users to redeem subscription offers that were no longer active. This issue is fixed in version 6.54.1.

Ghost is a Node.js content management system. From 0.10.0 until 6.54.1, a Server-Side Request Forgery in Ghost Admin image fetching allowed any staff-level user to perform a blind HTTP GET request against internal hosts. No output was returned, but this could have been used to probe open ports on internal hosts. This issue is fixed in version 6.54.1.