CVE-2025-31434: FormLift Infusionsoft XSS Vulnerability

CVE-2025-31434 Overview

CVE-2025-31434 is a stored Cross-Site Scripting (XSS) vulnerability in the FormLift for Infusionsoft Web Forms plugin by Adrian Tobey for WordPress. The flaw affects all plugin versions up to and including 7.5.19. It stems from improper neutralization of input during web page generation, classified under [CWE-79]. An authenticated attacker with low privileges can inject malicious scripts that persist in the application. When other users view the affected content, the payload executes in their browser context.

Critical Impact

Stored XSS enables attackers to execute arbitrary JavaScript in victim browsers, hijack sessions, and pivot toward administrative accounts within the WordPress environment.

Affected Products

• FormLift for Infusionsoft Web Forms plugin for WordPress
• All versions from initial release through 7.5.19
• WordPress sites using the vulnerable formlift plugin

Discovery Timeline

• 2025-03-28 - CVE-2025-31434 published to NVD
• 2026-06-17 - Last updated in NVD database

Technical Details for CVE-2025-31434

Vulnerability Analysis

The vulnerability resides in how the FormLift plugin processes user-supplied input before rendering it in web pages. The plugin fails to sanitize or encode input fields that are later stored and displayed in the browser. This creates a stored XSS condition where injected scripts persist across sessions and users.

Exploitation requires an authenticated user with at least contributor-level privileges. It also requires victim interaction, such as visiting a page containing the injected payload. The scope is changed, meaning the payload can affect resources beyond the vulnerable component, including administrator sessions and the WordPress admin dashboard.

Root Cause

The root cause is missing output encoding and input sanitization in the plugin's form rendering logic. The plugin trusts data submitted through form configuration fields and echoes it directly into HTML responses. Without applying WordPress functions such as esc_html(), esc_attr(), or wp_kses(), arbitrary HTML and JavaScript pass through to the browser and execute in the victim's session context.

Attack Vector

An attacker with a low-privileged authenticated account submits a crafted payload through a plugin field that lacks sanitization. The malicious content is stored in the WordPress database. When an administrator or other user loads the page containing the stored payload, the script executes in their browser. Attackers can use this to steal authentication cookies, perform actions on behalf of the victim, inject backdoors through plugin or theme editing, or redirect users to attacker-controlled infrastructure.

Refer to the Patchstack Vulnerability Report for additional technical context.

Detection Methods for CVE-2025-31434

Indicators of Compromise

• Unexpected <script> tags, event handlers, or javascript: URIs stored in FormLift form configuration entries within the WordPress database.
• Outbound browser requests from administrators to unknown domains shortly after visiting pages that render FormLift content.
• New or modified administrator accounts, plugin installations, or theme file edits following administrative sessions.
• Anomalous cookie or session token exfiltration patterns in web server or reverse proxy logs.

Detection Strategies

• Audit wp_posts, wp_postmeta, and plugin-specific tables for HTML or JavaScript patterns embedded in FormLift form fields.
• Deploy a web application firewall (WAF) rule set that identifies XSS payload signatures in POST requests targeting /wp-admin/ FormLift endpoints.
• Review WordPress audit logs for form creation or modification events performed by low-privileged accounts.

Monitoring Recommendations

• Enable a Content Security Policy (CSP) that blocks inline scripts and reports policy violations to a central endpoint.
• Forward WordPress access logs and admin activity to a centralized SIEM for correlation across authentication and content-change events.
• Alert on privilege changes, plugin installations, or user creation actions triggered from sessions that recently rendered FormLift pages.

How to Mitigate CVE-2025-31434

Immediate Actions Required

• Update the FormLift for Infusionsoft Web Forms plugin to a version above 7.5.19 as soon as a patched release is available from the vendor.
• Review all FormLift-managed forms for previously injected HTML or JavaScript payloads and remove any unexpected content.
• Rotate WordPress administrator passwords and invalidate active sessions if suspicious form content is discovered.
• Restrict form creation and editing permissions to trusted, high-trust user roles only.

Patch Information

At the time of publication, the vulnerability affects FormLift versions through 7.5.19. Consult the Patchstack Vulnerability Report and the plugin's official WordPress repository page for updated patch availability and release notes.

Workarounds

• Deactivate and remove the FormLift plugin until a patched version is confirmed.
• Deploy a WAF rule that blocks XSS payload patterns targeting FormLift administrative endpoints.
• Enforce a strict Content Security Policy that disallows inline scripts and untrusted script sources.
• Limit access to /wp-admin/ through IP allowlists or VPN gateways to reduce exposure of the vulnerable interface.

# Configuration example: enforce a restrictive Content Security Policy in Apache
Header set Content-Security-Policy "default-src 'self'; script-src 'self'; object-src 'none'; base-uri 'self'; frame-ancestors 'self'; report-uri /csp-report"