Craft is a platform for creating digital experiences. In Craft versions from 4.0.0-RC1 to before 4.17.0-beta.1 and 5.9.0-beta.1, there is a Privilege Escalation vulnerability in Craft CMS’s GraphQL API that allows an authenticated user with write access to one asset volume to escalate their privileges and modify/transfer assets belonging to any other volume, including restricted or private volumes to which they should not have access. The saveAsset GraphQL mutation validates authorization against the schema-resolved volume but fetches the target asset by ID without verifying that the asset belongs to the authorized volume. This allows unauthorized cross-volume asset modification and transfer. This vulnerability is fixed in 4.17.0-beta.1 and 5.9.0-beta.1.

Affected: Packagist: craftcms/cms

There is a Privilege Escalation vulnerability in Craft CMS’s GraphQL API that allows an authenticated user with write access to one asset volume to escalate their privileges and modify/transfer assets belonging to any other volume, including restricted or private volumes to which they should not have access.

## Summary:

Type: Privilege Escalation (CWE-269) Affected: Craft CMS 5.x (likely affects 4.x and 3.x as well) Location: `src/gql/resolvers/mutations/Asset.php lines 57-107`

## Root Cause:

The saveAsset GraphQL mutation validates authorization against the schema-resolved volume but fetches the target asset by ID without verifying that the asset belongs to the authorized volume. This allows unauthorized cross-volume asset modification and transfer.

## Impact:

- Transfer confidential assets from private volumes to public volumes (data exfiltration) - Modify asset metadata in restricted volumes - Bypass multi-tenant isolation in shared hosting environments