CVE-2024-49316: Akismet htaccess writer XSS Vulnerability

CVE-2024-49316 Overview

CVE-2024-49316 is a reflected Cross-Site Scripting (XSS) vulnerability in the akismet-htaccess-writer WordPress plugin developed by zodiac. The flaw affects all versions of Akismet htaccess writer up to and including 1.0.1. The plugin fails to properly neutralize user-supplied input before reflecting it back in generated web pages, classified under [CWE-79]. Attackers can craft malicious links that, when clicked by an authenticated user, execute arbitrary JavaScript in the victim's browser context. The vulnerability carries a CVSS 3.1 score of 7.1 and requires user interaction to exploit.

Critical Impact

Successful exploitation allows attackers to execute arbitrary JavaScript in a victim's browser session, leading to session theft, credential harvesting, or actions performed on behalf of the targeted user.

Affected Products

• Akismet htaccess writer plugin for WordPress
• All versions from n/a through 1.0.1
• WordPress installations with the akismet-htaccess-writer plugin enabled

Discovery Timeline

• 2024-10-17 - CVE-2024-49316 published to NVD
• 2026-04-29 - Last updated in NVD database

Technical Details for CVE-2024-49316

Vulnerability Analysis

The vulnerability stems from improper neutralization of user-controlled input during web page generation in the Akismet htaccess writer plugin. The plugin reflects untrusted request parameters back into the HTTP response without applying contextual output encoding or input sanitization. An attacker delivers a crafted URL to a target who interacts with the plugin interface, typically a site administrator. The browser then parses the injected payload as part of the page DOM and executes it.

Because the issue requires user interaction and operates across a security scope boundary, the impact extends beyond the vulnerable component to affect the broader WordPress administrative session. Confidentiality, integrity, and availability impacts are each rated low individually but compound when chained with administrative privileges, enabling session hijacking, malicious redirects, and unauthorized configuration changes.

Root Cause

The root cause is missing output encoding on reflected request parameters within the plugin's administrative or front-end handlers. WordPress provides functions such as esc_html(), esc_attr(), and wp_kses() to enforce contextual escaping, but the affected code paths in akismet-htaccess-writer versions ≤ 1.0.1 omit these calls. Input flows directly from the HTTP request into the rendered HTML response.

Attack Vector

Exploitation requires the attacker to deliver a crafted URL to an authenticated WordPress user with access to the plugin. Common delivery vectors include phishing emails, malicious referrers, or social engineering through site comments. Upon click, the victim's browser submits the malicious parameter, the server reflects it into the response, and the injected script executes under the WordPress origin. No authentication is required from the attacker, but the victim must be logged in for the payload to access sensitive session data. Refer to the Patchstack Vulnerability Advisory for technical details.

Detection Methods for CVE-2024-49316

Indicators of Compromise

• HTTP requests to plugin endpoints containing <script>, javascript:, onerror=, or onload= substrings in query parameters
• Unexpected outbound requests from administrator browsers to attacker-controlled domains after visiting WordPress admin pages
• New or modified .htaccess rules that were not authorized by site administrators
• WordPress audit logs showing administrative actions originating from unusual IP addresses or sessions

Detection Strategies

• Inspect web server access logs for request URIs targeting akismet-htaccess-writer plugin paths with encoded or raw HTML/JavaScript payloads
• Deploy a web application firewall rule set that flags reflected XSS patterns in plugin parameters
• Correlate WordPress session events with referrer headers pointing to untrusted external domains

Monitoring Recommendations

• Enable WordPress activity logging plugins to track administrator actions and configuration changes
• Monitor file integrity on .htaccess and plugin directories for unexpected modifications
• Alert on Content Security Policy (CSP) violation reports referencing inline script execution on admin pages

How to Mitigate CVE-2024-49316

Immediate Actions Required

• Deactivate and remove the akismet-htaccess-writer plugin until a patched version is available
• Audit administrator accounts and force password rotation for any user who may have clicked suspicious links
• Invalidate active WordPress sessions by rotating authentication keys and salts in wp-config.php
• Review .htaccess files for unauthorized rules introduced through exploitation

Patch Information

No fixed version has been published at the time of CVE assignment. The vulnerability affects all releases through 1.0.1, and no later patched release is referenced in the Patchstack Vulnerability Advisory. Administrators should remove the plugin until the vendor releases a fix.

Workarounds

• Remove the plugin entirely and rely on the official Akismet Anti-Spam plugin without the htaccess writer extension
• Deploy a web application firewall with managed rules that block reflected XSS payloads targeting WordPress plugins
• Enforce a strict Content Security Policy that disallows inline scripts and restricts script sources to trusted origins
• Train administrators to avoid clicking unsolicited links pointing to their own WordPress admin domain

# Disable the vulnerable plugin via WP-CLI
wp plugin deactivate akismet-htaccess-writer
wp plugin delete akismet-htaccess-writer

# Rotate WordPress authentication salts to invalidate sessions
wp config shuffle-salts