CVE-2025-31407: Tiger Stored XSS Vulnerability

CVE-2025-31407 Overview

CVE-2025-31407 is a stored Cross-Site Scripting (XSS) vulnerability in the hutsixdigital Tiger WordPress theme. The flaw affects Tiger versions up to and including 2.0 and stems from improper neutralization of user input during web page generation [CWE-79]. Authenticated attackers with low privileges can inject malicious JavaScript payloads that persist in the application and execute in the browsers of visitors and administrators. The vulnerability is tracked under the WordPress theme security database maintained by Patchstack.

Critical Impact

Attackers with low-privilege authenticated access can inject persistent JavaScript that executes in other users' browsers, enabling session theft, administrative account takeover, and redirection to attacker-controlled infrastructure.

Affected Products

• hutsixdigital Tiger WordPress theme versions up to and including 2.0
• WordPress installations using the Tiger theme as the active or fallback theme
• Sites where low-privileged users can submit content rendered by the theme

Discovery Timeline

• 2025-04-04 - CVE-2025-31407 published to the National Vulnerability Database
• 2026-06-17 - Last updated in NVD database

Technical Details for CVE-2025-31407

Vulnerability Analysis

The Tiger theme fails to sanitize or encode user-supplied input before rendering it within web page output. This omission allows attackers to store crafted HTML or JavaScript payloads inside theme-controlled fields. When another user loads the affected page, the browser parses the injected content as executable script rather than inert data.

Stored XSS in a WordPress theme is particularly impactful because injected payloads persist across sessions and reach any visitor of the affected page. Attackers can weaponize the flaw to hijack administrator sessions, plant persistent backdoors through the WordPress REST API, or pivot into plugin management functionality. Exploitation requires user interaction, typically a victim loading the page containing the stored payload.

Root Cause

The root cause is missing output encoding and input sanitization in code paths that render user-controlled data. WordPress provides helper functions such as esc_html(), esc_attr(), and wp_kses_post() for context-aware escaping. The Tiger theme did not consistently apply these functions before echoing values into the page, allowing raw HTML and <script> tags to reach the DOM.

Attack Vector

The attack requires network access and low-privileged authentication to the WordPress site. An attacker submits input containing HTML or JavaScript through a theme-exposed field. The payload is stored server-side and later rendered without escaping. A victim, including administrators, triggers execution by simply viewing the affected page. Because the scope is changed, the injected script runs in the context of the vulnerable site and can access resources beyond the attacker's original privilege level.

See the Patchstack Tiger Theme XSS advisory for additional technical context.

Detection Methods for CVE-2025-31407

Indicators of Compromise

• Unexpected <script>, <iframe>, or event-handler attributes (onload, onerror, onclick) stored in WordPress database tables such as wp_posts, wp_postmeta, or theme option rows
• Outbound requests from visitor browsers to unfamiliar domains after loading Tiger theme pages
• New or modified WordPress administrator accounts without corresponding audit trail entries
• Session cookies transmitted to external hosts observed in web proxy or DNS logs

Detection Strategies

• Scan the WordPress database for suspicious HTML tags and JavaScript payloads in fields consumed by the Tiger theme
• Deploy a Web Application Firewall (WAF) rule set that flags XSS patterns in POST requests to /wp-admin/ and theme-specific endpoints
• Review WordPress activity logs for content edits by low-privileged accounts that touch theme-rendered fields

Monitoring Recommendations

• Enable Content Security Policy (CSP) reporting to capture script execution violations originating from injected payloads
• Forward WordPress access, error, and audit logs to a centralized SIEM for correlation across authentication and content events
• Monitor for anomalous administrator session activity, including logins from new geolocations or unusual API usage patterns

How to Mitigate CVE-2025-31407

Immediate Actions Required

• Update the Tiger theme to a version later than 2.0 once the vendor publishes a patched release
• Audit all user accounts with content submission privileges and disable or reset any that appear compromised
• Inspect the database for previously injected payloads and remove malicious HTML or JavaScript from stored content
• Rotate WordPress administrator credentials and invalidate active sessions to defeat stolen session cookies

Patch Information

As of the last NVD update on 2026-06-17, the advisory documents the vulnerability affecting Tiger through version 2.0. Consult the Patchstack advisory for the current patched version and vendor guidance. Apply the update in a staging environment first, then promote to production.

Workarounds

• Deactivate the Tiger theme and switch to a maintained alternative until a patched version is available
• Restrict content submission and user registration to trusted accounts only
• Deploy a WordPress-aware WAF with signatures for stored XSS payloads targeting theme fields
• Implement a strict Content Security Policy that blocks inline scripts and restricts script sources to allowlisted origins

# Example strict Content Security Policy header for WordPress (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"