On October 1, 2025, Palantir discovered that images uploaded through the Dossier front-end app were not being marked correctly with the proper security levels. The regression was traced back to a change in May 2025, which was meant to allow file uploads to be shared among different artifacts (e.g. other dossiers and presentations).
On deployments configured with CBAC, the front-end would present a security picker dialog to set the security level on the uploads, thereby mitigating the issue.
On deployments without a CBAC configuration, no security picker dialog appears, leading to a security level of CUSTOM with no markings or datasets selected. The resulting markings and groups for the file uploads thus will be only those added by the default authorization rules defined in the Auth Chooser configuration. On most environments, it is expected that the default authorization rules only add the Everyone group.
Weakness
The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check.
Potential Mitigations
- Divide the product into anonymous, normal, privileged, and administrative areas. Reduce the attack surface by carefully mapping roles with data and functionality. Use role-based access control (RBAC) [REF-229] to enforce the roles at the appropriate boundaries.
- Note that this approach may not protect against horizontal authorization, i.e., it will not protect a user from attacking others with the same role.
- Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
- For example, consider using authorization frameworks such as the JAAS Authorization Framework [REF-233] and the OWASP ESAPI Access Control feature [REF-45].
- For web applications, make sure that the access control mechanism is enforced correctly at the server side on every page. Users should not be able to access any unauthorized functionality or information by simply requesting direct access to that page.
- One way to do this is to ensure that all pages containing sensitive information are not cached, and that all such pages restrict access to requests that are accompanied by an active and authenticated session token associated with a user who has the required permissions to access that page.