CVE-2025-48270: SKT Blocks DOM-Based XSS Vulnerability

CVE-2025-48270 Overview

CVE-2025-48270 is a DOM-based cross-site scripting (XSS) vulnerability in the SKT Blocks WordPress plugin by sonalsinha21. The flaw affects all versions of SKT Blocks through 2.2 and stems from improper neutralization of input during web page generation [CWE-79]. An authenticated attacker with low privileges can inject malicious scripts that execute in the context of a victim's browser when the victim interacts with a crafted link or page element. Because the issue has a scope change (S:C), the injected script can affect resources beyond the vulnerable component, impacting other users of the WordPress site.

Critical Impact
Authenticated attackers can execute arbitrary JavaScript in victims' browsers, enabling session theft, account takeover, and WordPress admin compromise through social-engineered interaction.

Affected Products

SKT Blocks (skt-blocks) WordPress plugin by sktthemes
All versions from initial release through 2.2 (inclusive)
WordPress sites with the vulnerable plugin installed and activated

Discovery Timeline

2025-05-19 - CVE-2025-48270 published to the National Vulnerability Database
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2025-48270

Vulnerability Analysis

The vulnerability is a DOM-based XSS flaw in the SKT Blocks plugin, a Gutenberg block collection for WordPress. DOM-based XSS occurs when client-side JavaScript writes attacker-controlled data into the Document Object Model (DOM) without proper sanitization or encoding. Unlike reflected or stored XSS, the malicious payload is processed entirely in the browser, often without reaching the server in an obvious form.

Exploitation requires both low-privilege authentication (PR:L) and user interaction (UI:R), such as a victim clicking a crafted link or loading a page with manipulated block content. Successful exploitation delivers partial confidentiality and integrity impact, and because scope changes, the executed JavaScript can act against other site components, including administrative interfaces.

Root Cause

The root cause is missing output encoding or input sanitization in the plugin's client-side JavaScript when rendering block attributes into the DOM. Attacker-controlled values flow from a source (such as location.hash, URL parameters, or stored block attributes) into a sink (such as innerHTML or document.write) without being neutralized. This allows HTML and script content to be interpreted rather than rendered as text.

Attack Vector

An attacker with a low-privileged account, such as Contributor or Author, can craft block content containing a malicious payload. When another user, typically an Editor or Administrator, previews or edits the content, the payload executes in their browser session. The attacker can then exfiltrate session cookies, perform actions on behalf of the victim, or pivot to further compromise the WordPress installation.

No verified public exploit code is available for CVE-2025-48270. For technical details, see the Patchstack XSS Vulnerability Advisory.

Detection Methods for CVE-2025-48270

Indicators of Compromise

Unexpected <script> tags, event handlers (onerror, onload), or javascript: URIs embedded in post content, block attributes, or wp_postmeta entries
Outbound HTTP requests from administrator browsers to unfamiliar domains shortly after loading plugin-rendered content
Creation of unauthorized administrator accounts or modifications to user roles following interaction with SKT Blocks content

Detection Strategies

Audit WordPress database tables (wp_posts, wp_postmeta) for block markup containing suspicious HTML or JavaScript patterns associated with SKT Blocks
Deploy a web application firewall (WAF) with rules that flag XSS payloads in POST requests to WordPress REST API endpoints and admin-ajax handlers
Review the installed SKT Blocks version via wp-admin/plugins.php and flag any instance at or below version 2.2

Monitoring Recommendations

Enable WordPress audit logging to track content edits, user role changes, and plugin activity by low-privilege accounts
Monitor browser Content Security Policy (CSP) violation reports to identify attempts to execute inline or external scripts
Correlate authentication events from Contributor and Author accounts with subsequent administrator session activity

How to Mitigate CVE-2025-48270

Immediate Actions Required

Identify all WordPress sites running SKT Blocks version 2.2 or earlier and prioritize them for patching
Restrict new Contributor and Author account registrations until the plugin is updated or removed
Review existing low-privilege accounts for suspicious content submissions and remove untrusted entries

Patch Information

At the time of writing, the Patchstack advisory lists versions through 2.2 as affected. Administrators should consult the Patchstack XSS Vulnerability Advisory and the plugin's official repository for the latest patched release. Update to the fixed version as soon as it is published by the vendor.

Workarounds

Deactivate and remove the SKT Blocks plugin until a patched version is available
Enforce a strict Content Security Policy that disallows inline scripts and restricts script sources to trusted origins
Limit editing privileges for untrusted users and require administrator review before publishing content that uses SKT Blocks

bash

# Example: disable the SKT Blocks plugin via WP-CLI
wp plugin deactivate skt-blocks
wp plugin delete skt-blocks

# Example: enforce a restrictive Content Security Policy via .htaccess
Header set Content-Security-Policy "default-src 'self'; script-src 'self'; object-src 'none'; base-uri 'self'"