Auth bypass in Trainingbusinesspros Formlift For Infusionsoft Web Forms
CVE-2026-4281
The FormLift for Infusionsoft Web Forms plugin for WordPress is vulnerable to Missing Authorization in all versions up to, and including, 7.5.21. This is due to missing capability checks on the connect() and listen_for_tokens() methods of the FormLift_Infusionsoft_Manager class, both of which are hooked to 'plugins_loaded' and execute on every page load. The connect() function generates an OAuth connection password and leaks it in the redirect Location header without verifying the requesting user is authenticated or authorized. The listen_for_tokens() function only validates the temporary password but performs no user authentication before calling update_option() to save attacker-controlled OAuth tokens and app domain. This makes it possible for unauthenticated attackers to hijack the site's Infusionsoft connection by first triggering the OAuth flow to obtain the temporary password, then using that password to set arbitrary OAuth tokens and app domain via update_option(), effectively redirecting the plugin's API communication to an attacker-controlled server.
Vulnerability class: Broken Access Control
EPSS: 0.005 (38.4th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.
Affected products
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-4281?
- CVE-2026-4281 is a medium-severity vulnerability in Trainingbusinesspros Formlift For Infusionsoft Web Forms, classified under Missing Authorization. CVSS score: 5.3/10. Published 2026-03-26.
- How severe is CVE-2026-4281?
- Medium severity. CVSS v3 base score is 5.3 out of 10.