App Builder <= 5.5.10 - Insecure Direct Object Reference to Authenticated (Subscriber+) Arbitrary User Avatar Modification via 'user_id' Parameter
Affected versions: *-5.6.0
Vulnerability type: CWE-639 Authorization Bypass Through User-Controlled Key
Affected software, patched versions and attribution
The App Builder – Create Native Android & iOS Apps On The Flight plugin for WordPress is vulnerable to Insecure Direct Object Reference in all versions up to and including 5.6.0. This is due to missing authorization validation in the `upload_avatar()` function, which accepts an attacker-controlled `user_id` parameter from the POST request body and uses it to update user meta without verifying that the authenticated requester owns or has permission to modify the target account. This makes it possible for authenticated attackers, with Subscriber-level access and above, to overwrite the profile avatar of any arbitrary user on the site, including administrators, by supplying a target `user_id` in the request body to the `/wp-json/app-builder/v1/upload-avatar` endpoint.
App Builder – Create Native Android & iOS Apps On The Flight
Affected versions: *-5.6.0
Patched versions: Not supplied
Researcher credit: Ren Voza
Applicable copyright and licence notices
This record contains material that is subject to copyright
Copyright 2012-2026 Defiant Inc.
Defiant hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute this software vulnerability information. Any copy of the software vulnerability information you make for such purposes is authorized provided that you include a hyperlink to this vulnerability record and reproduce Defiant's copyright designation and this license in any such copy.
This record contains material that is subject to copyright
Copyright 1999-2026 The MITRE Corporation
CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE®). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy.
- Published
- May 1, 2026
- CVSS
- 5.3