CVE-2025-12645 Overview
CVE-2025-12645 is a Stored Cross-Site Scripting (XSS) vulnerability in the Inline frame – Iframe plugin for WordPress. The flaw affects all versions up to and including 0.1. It resides in the embedsite shortcode, which fails to properly sanitize user-supplied attributes before rendering them in page output. Authenticated attackers with contributor-level access or higher can inject arbitrary JavaScript into WordPress pages. The injected scripts execute in the browser of any visitor who views the affected page, enabling session theft, redirection, and administrative actions in the context of higher-privileged users.
Critical Impact
Contributor-level accounts can plant persistent JavaScript payloads that execute against site administrators and visitors, leading to account takeover and site compromise.
Affected Products
- WordPress Inline frame – Iframe plugin, versions up to and including 0.1
- WordPress sites that expose contributor-level registration or accept guest contributors
- Sites relying on the vulnerable embedsite shortcode implementation in iframe.php
Discovery Timeline
- 2025-11-25 - CVE-2025-12645 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-12645
Vulnerability Analysis
The vulnerability is classified as Cross-Site Scripting [CWE-79]. The Inline frame – Iframe plugin registers an embedsite shortcode that accepts user-controlled attributes and outputs them directly into HTML markup. The plugin does not apply WordPress escaping functions such as esc_attr() or esc_url() to those attributes before rendering. Any authenticated user with the ability to author posts or pages can embed the shortcode with attacker-controlled values. When a visitor or administrator loads the page, the browser parses the injected markup and executes attacker-supplied JavaScript. Because the payload is stored server-side inside post content, exploitation is persistent and does not require additional social engineering after publication.
Root Cause
The root cause is insufficient input sanitization and output escaping in the embedsite shortcode handler. The plugin trusts shortcode attributes provided by contributors and concatenates them into the generated <iframe> markup. Standard WordPress capability checks are bypassed because contributors are already authorized to submit content, and the shortcode processor does not validate attribute values against an allowlist or HTML-encode them before output. Technical detail is available in the WordPress Plugin Code Review and the Wordfence Vulnerability Analysis.
Attack Vector
An attacker first obtains contributor-level access, either through legitimate registration on sites that allow it or through credential compromise. The attacker then creates or edits a post containing the embedsite shortcode with malicious attribute values, such as JavaScript URIs or attributes that break out of the intended HTML context. When the post is previewed by a reviewing editor or published and viewed by visitors, the injected script runs in the victim's browser session. The attacker can steal authentication cookies, hijack administrator sessions, inject rogue administrator accounts, or pivot to further site compromise.
No verified public exploit code has been released for CVE-2025-12645. See the referenced advisories for technical details on the vulnerable shortcode implementation.
Detection Methods for CVE-2025-12645
Indicators of Compromise
- Post or page content containing the embedsite shortcode with unusual attribute values, script tags, or javascript: URIs
- Unexpected contributor or author accounts created shortly before suspicious post edits
- Outbound requests from administrator browsers to attacker-controlled domains after viewing plugin-rendered pages
Detection Strategies
- Inspect the wp_posts table for shortcode usage combined with HTML event handlers such as onerror, onload, or onmouseover
- Review WordPress audit logs for post edits performed by contributor-level users that include iframe or script content
- Scan rendered page output for iframe elements referencing untrusted origins or containing inline JavaScript
Monitoring Recommendations
- Enable WordPress activity logging to track contributor post submissions and content changes
- Monitor administrator sessions for anomalous API calls to /wp-json/wp/v2/users that create new privileged accounts
- Alert on Content Security Policy violations reported by browsers when viewing plugin-rendered pages
How to Mitigate CVE-2025-12645
Immediate Actions Required
- Deactivate and remove the Inline frame – Iframe plugin until a patched version is published
- Audit all posts and pages for existing embedsite shortcode usage and remove any suspicious attribute values
- Restrict contributor-level registration and review recently created low-privilege accounts
Patch Information
At the time of NVD publication, no fixed version of the Inline frame – Iframe plugin is listed. All versions up to and including 0.1 remain vulnerable. Site operators should track the Wordfence Vulnerability Analysis for patch availability and update guidance.
Workarounds
- Remove the plugin entirely and replace embedded content with hard-coded iframes managed by editor-level users or above
- Deploy a Web Application Firewall rule that blocks shortcode attributes containing <script>, javascript:, or HTML event handlers
- Enforce a strict Content Security Policy that disallows inline scripts and untrusted iframe sources
# Configuration example: disable the vulnerable plugin via WP-CLI
wp plugin deactivate inline-frame-iframe
wp plugin delete inline-frame-iframe
# Audit posts for the vulnerable shortcode
wp db query "SELECT ID, post_title, post_author FROM wp_posts WHERE post_content LIKE '%[embedsite%';"
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
