Is App Builder safe? Known vulnerabilities and latest version

The App Builder WordPress plugin before 5.7.1 does not require authentication or authorisation before writing attacker-supplied data to one of its options and, on a separate unauthenticated request, redirecting the visitor's browser to a URI built from that stored data.

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.

The App Builder – Create Native Android & iOS Apps On The Flight plugin for WordPress is vulnerable to Privilege Escalation in all versions up to, and including, 5.5.10. This is due to the `verify_role()` function in `AuthTrails.php` explicitly whitelisting the `wcfm_vendor` role alongside `subscriber` and `customer`, and assigning it directly via `wp_insert_user()` without integrating with WCFM Marketplace's vendor approval workflow. This makes it possible for unauthenticated attackers to register an account with the `wcfm_vendor` role by supplying the `role` parameter in the `/wp-json/app-builder/v1/register` REST API endpoint, bypassing the standard WCFM vendor approval process and immediately gaining vendor-level privileges (product management, order access, store management) on sites where WCFM Marketplace is active.

Missing Authorization vulnerability in App Cheap App Builder app-builder allows Exploiting Incorrectly Configured Access Control Security Levels.This issue affects App Builder: from n/a through <= 5.5.6.

The App Builder – Create Native Android & iOS Apps On The Flight plugin for WordPress is vulnerable to privilege escalation via account takeover in all versions up to, and including, 5.3.7. This is due to the verify_otp_forgot_password() and update_password() functions not having enough controls to prevent a successful brute force attack of the OTP to change a password, or verify that a password reset request came from an authorized user. This makes it possible for unauthenticated attackers to generate and brute force an OTP that makes it possible to change any users passwords, including an administrator.

The App Builder – Create Native Android & iOS Apps On The Flight plugin for WordPress is vulnerable to limited SQL Injection via the ‘app-builder-search’ parameter in all versions up to, and including, 4.2.6 due to insufficient escaping on the user supplied parameter and lack of sufficient preparation on the existing SQL query. This makes it possible for unauthenticated attackers to append additional SQL queries into already existing queries that can be used to extract sensitive information from the database.

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Appcheap.Io App Builder allows Stored XSS.This issue affects App Builder: from n/a through 3.8.8.

URL Redirection to Untrusted Site ('Open Redirect') vulnerability in Appcheap.Io App Builder.This issue affects App Builder: from n/a through 3.8.7.