Advanced Custom Fields v6.8.10

Release Date 10th September 2026

• Security - ACF now validates that uploaded PDF files begin with the standard %PDF- header before further processing, rejecting files that do not match the expected format
• Security - The Relationship, Post Object, Image, Gallery, and File fields now enforce WordPress read permissions on referenced posts and attachments when returned in REST API responses
• Security - ACF now verifies both preview context and the caller's edit capability before substituting revision data when field values are retrieved for a post
• Security - The _acf_form token used by frontend forms now expires and is bound to its issuing render, and acf_encrypt() / acf_decrypt() gain an optional $context argument for domain separation between token uses
• Security - ACF now consistently runs field validation on frontend form submissions containing field data, ensuring required-field checks and custom acf/validate_value filters cannot be circumvented
• Security - ACF's REST API schema no longer discloses per-object field-group configuration in OPTIONS requests to callers who lack read permission on the target object
• Security - The User field AJAX endpoint now validates that the request nonce was created for a User field