Advanced Form Integration <= 2.6.0 - Missing Authorization to Authenticated (Subscriber+) Arbitrary MailUp OAuth Token Overwrite via auth_redirect() Function
Strategic Overview
- Status
- Patched in 2.7.0
- Affected Plugin
- Advanced Form Integration — Connect Forms to 300+ Apps
- Affected Version
<= 2.6.0- CVSS
- 4.3Medium
- Weakness type
- CWE-862 · Missing Authorization
- CVE
CVE-2026-16587
At a glance
CVE-2026-16587 is a medium-severity Missing Authorization vulnerability in the Advanced Form Integration WordPress plugin, affecting versions <= 2.6.0. It carries a CVSS score of 4.3 (reachable over the network; low attack complexity). Exploitation requires an authenticated account at Subscriber level or above. The issue is fixed in version 2.7.0; sites on affected versions should update now. Disclosed July 2026, reported by Wordfence PRISM.
Vulnerability Overview
The Advanced Form Integration — Connect Forms to 200+ Apps plugin for WordPress is vulnerable to authorization bypass in all versions up to, and including, 2.6.0. This is due to the plugin not properly verifying that a user is authorized to perform an action. This makes it possible for authenticated attackers, with subscriber-level access and above, to overwrite the site's stored MailUp OAuth tokens in the adfoin_mailup_keys option with attacker-controlled tokens, hijacking future form-submission data to a MailUp account they control or nulling the tokens to break the integration entirely. This is exploitable by any authenticated user who can reach /wp-admin/profile.php, as admin_init fires for all logged-in users visiting any wp-admin page.
Technical Analysis
The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no interaction from a victim user.
CWE-862: Missing Authorization
Reaching this weakness in Advanced Form Integration <= 2.6.0 takes an account at Subscriber level or above. A missing authorization check means a function is reachable by anyone who can reach the endpoint, because the code never asks whether the caller is allowed to perform the action.
Any user who can reach the endpoint gets to run an action reserved for higher-privileged roles, from reading protected data to changing settings or content. For Advanced Form Integration the fix is 2.7.0: builds <= 2.6.0 are affected, anything from 2.7.0 onward is not.
Remediation
Update to version 2.7.0, or a newer patched version
How does WordSec protect against this?
Because it turns on account access, WordSec's login security is the relevant layer: role-based two-factor, captcha and brute-force limits raise the cost of getting the account this needs. None of that substitutes for the fix: Advanced Form Integration 2.7.0 closes this, and updating the plugin is the step that ends it.
- Login Security
- Alerts
External References
Related records
Same weakness class
Other vulnerabilities in Advanced Form Integration — Connect Forms to 300+ Apps
- 8.1CVE-2026-11794: Advanced Form Integration Privilege Escalation
CVE-2026-11794 - 6.6CVE-2023-50853: Advanced Form Integration <= 1.75.0 SQL Injection
CVE-2023-50853 - 6.1CVE-2024-10877: AFI – The Easiest Integration Plugin Reflected XSS
CVE-2024-10877 - 6.1CVE-2024-2387: Advanced Form Integration SQL Injection
CVE-2024-2387 - 6.1CVE-2023-33999: Freemius SDK <= 2.5.9 Reflected Cross-Site Scripting
CVE-2023-33999 - 4.4CVE-2024-13123: AFI – The Easiest Integration Plugin Stored XSS
CVE-2024-13123 - 4.4CVE-2024-13122: AFI – The Easiest Integration Plugin Stored XSS
CVE-2024-13122 - 4.4CVE-2024-56293: Advanced Form Integration <= 1.95.0 Stored XSS
CVE-2024-56293
Vulnerability data © Defiant, Inc., provided under the Wordfence Intelligence T&C