CVE-2025-12895: Kalium WordPress Theme Auth Bypass Flaw

CVE-2025-12895 Overview

The Kalium 3 | Creative WordPress & WooCommerce Theme for WordPress contains an authorization bypass vulnerability due to a missing capability check on the kalium_vc_contact_form_request() function. This flaw exists in all versions up to and including version 3.29. The vulnerability allows unauthenticated attackers to exploit the theme as an open mail relay, enabling them to send emails to arbitrary addresses using the server's identity.

Critical Impact

Unauthenticated attackers can abuse the vulnerable WordPress theme to send spam or phishing emails through the server, potentially damaging the server's reputation and causing email delivery issues for legitimate communications.

Affected Products

• Kalium 3 | Creative WordPress & WooCommerce Theme versions up to and including 3.29
• WordPress installations running vulnerable Kalium theme versions
• WooCommerce sites using the affected Kalium theme

Discovery Timeline

• 2026-01-15 - CVE CVE-2025-12895 published to NVD
• 2026-01-16 - Last updated in NVD database

Technical Details for CVE-2025-12895

Vulnerability Analysis

This vulnerability is classified as CWE-862 (Missing Authorization). The core issue stems from the kalium_vc_contact_form_request() function failing to implement proper capability checks before processing email-sending requests. In WordPress development, capability checks are essential security controls that verify whether a user has the appropriate permissions to perform a given action.

Without this check, the function accepts and processes email requests from any user, including unauthenticated visitors. This creates an open mail relay condition where attackers can craft malicious requests to send emails through the WordPress server to any destination address of their choosing.

The network-accessible nature of this vulnerability means attackers can exploit it remotely without requiring any prior authentication or user interaction. The impact is primarily on integrity, as attackers can send unauthorized communications that appear to originate from the vulnerable server.

Root Cause

The root cause is the absence of a capability verification mechanism in the kalium_vc_contact_form_request() function. WordPress provides functions such as current_user_can() to check user capabilities before executing privileged operations. The vulnerable code path allows the email-sending functionality to execute without first confirming that the requesting user has legitimate permissions to send emails through the contact form handler.

Attack Vector

The attack is carried out over the network by sending specially crafted HTTP requests to the WordPress installation running the vulnerable Kalium theme. An attacker identifies a target site using the Kalium theme and sends POST requests to the contact form endpoint. Because no capability check exists, the server processes these requests and sends emails to attacker-specified recipients.

This turns the WordPress server into an unwitting spam or phishing relay. The attacker can specify arbitrary recipient addresses, custom message content, and potentially manipulate other email parameters. Since the emails originate from the legitimate WordPress server, they may bypass spam filters and carry the reputation of the compromised domain.

Detection Methods for CVE-2025-12895

Indicators of Compromise

• Unusual volume of outbound emails from the WordPress server
• Email queue containing messages to unfamiliar or suspicious recipient addresses
• Web server logs showing unexpected POST requests to contact form endpoints
• Mail server logs indicating emails sent without corresponding legitimate form submissions
• Bounce-back or delivery failure notifications for emails you didn't send

Detection Strategies

• Monitor web application firewall (WAF) logs for anomalous POST requests targeting /wp-admin/admin-ajax.php with contact form actions
• Implement rate limiting on the contact form endpoint to detect and block high-volume abuse attempts
• Review email server logs for unusual sending patterns, particularly high volumes to external domains
• Set up alerts for outbound email volume thresholds being exceeded

Monitoring Recommendations

• Enable detailed logging for the WordPress mail function and contact form submissions
• Configure email server monitoring to track outbound message volume and recipient patterns
• Deploy network monitoring to detect unusual SMTP traffic from the WordPress server
• Use SentinelOne Singularity platform to monitor for suspicious process behavior and network communications from web server processes

How to Mitigate CVE-2025-12895

Immediate Actions Required

• Update the Kalium theme to version 3.30 or later immediately
• Audit email server logs for signs of prior exploitation or abuse
• Check server IP reputation on blacklists and submit delisting requests if necessary
• Temporarily disable the contact form functionality if immediate patching is not possible

Patch Information

Laborator has released an update addressing this vulnerability. Users should update to version 3.30 or later of the Kalium theme. The changelog and update information can be found at the Laborator Kalium Changelog. Additional vulnerability details are available in the Wordfence Vulnerability Report.

Workarounds

• Implement a WordPress security plugin that adds capability checks to AJAX handlers
• Use a web application firewall (WAF) to rate-limit and filter requests to the contact form endpoint
• Configure server-level email sending restrictions to limit outbound email volume
• Disable the Visual Composer contact form module until the patch is applied

# Configuration example
# Add to wp-config.php to limit email sending (temporary mitigation)
# This restricts WordPress mail to specific domains
define('WP_MAIL_CONTENT_TYPE', 'text/html');

# In .htaccess, rate limit the admin-ajax.php endpoint
# <Files admin-ajax.php>
#   SetEnvIfNoCase Request_URI "\.php$" rate-limit
# </Files>