CVE-2026-28068: ThemeREX Rhythmo File Inclusion Flaw

CVE-2026-28068 Overview

CVE-2026-28068 is a Local File Inclusion (LFI) vulnerability affecting the ThemeREX Rhythmo WordPress theme. The vulnerability stems from improper control of filename parameters in PHP include/require statements, allowing attackers to include arbitrary local files from the server filesystem. This weakness (CWE-98) can lead to information disclosure, configuration file exposure, and potentially remote code execution when combined with other techniques such as log poisoning or file upload vulnerabilities.

Critical Impact

Unauthenticated attackers may exploit this vulnerability to read sensitive server files, extract credentials from configuration files, or achieve code execution by including files containing malicious PHP code.

Affected Products

• ThemeREX Rhythmo WordPress Theme versions up to and including 1.3.4

Discovery Timeline

• 2026-03-05 - CVE-2026-28068 published to NVD
• 2026-03-05 - Last updated in NVD database

Technical Details for CVE-2026-28068

Vulnerability Analysis

This vulnerability falls under CWE-98 (Improper Control of Filename for Include/Require Statement in PHP Program). The Rhythmo WordPress theme fails to properly sanitize user-supplied input before using it in PHP include() or require() functions. This allows an attacker to manipulate the file path parameter to traverse directories and include arbitrary files from the local filesystem.

The attack can be executed remotely over the network, though it requires specific conditions to be met, making exploitation complexity higher. Successfully exploiting this vulnerability can result in complete compromise of confidentiality, integrity, and availability of the affected WordPress installation.

Root Cause

The root cause of CVE-2026-28068 is insufficient input validation and sanitization of user-controllable parameters that are passed to PHP file inclusion functions. The vulnerable code path does not adequately filter directory traversal sequences (such as ../) or validate that the included file resides within an expected directory, allowing attackers to escape the intended directory context.

Attack Vector

The vulnerability is exploitable via network-based attack vectors without requiring authentication. An attacker can craft malicious HTTP requests containing path traversal sequences to manipulate the file inclusion logic. Common exploitation scenarios include:

• Reading sensitive configuration files such as wp-config.php to extract database credentials
• Accessing system files like /etc/passwd on Unix-based systems
• Including log files that have been poisoned with PHP code to achieve code execution
• Reading other plugin or theme files that may contain sensitive information

The attack requires the attacker to identify the vulnerable parameter and construct appropriate path traversal payloads based on the server's directory structure.

Detection Methods for CVE-2026-28068

Indicators of Compromise

• Unusual HTTP requests containing path traversal sequences (../, ..%2f, ..%252f) in GET or POST parameters
• Access log entries showing attempts to include system files or WordPress configuration files
• Requests targeting theme-specific endpoints with file path manipulation patterns
• Error log entries indicating failed file inclusion attempts with unexpected paths

Detection Strategies

• Configure web application firewall (WAF) rules to detect and block path traversal patterns in request parameters
• Implement SIEM rules to alert on patterns of directory traversal attempts in web server logs
• Monitor for access to sensitive files from unexpected sources or processes
• Deploy file integrity monitoring on critical configuration files to detect unauthorized access

Monitoring Recommendations

• Enable verbose logging for the web server and review logs regularly for suspicious file access patterns
• Set up alerts for repeated 404/500 errors that may indicate exploitation attempts
• Monitor WordPress theme file access patterns for anomalies
• Implement runtime application self-protection (RASP) to detect file inclusion attacks in real-time

How to Mitigate CVE-2026-28068

Immediate Actions Required

• Update the ThemeREX Rhythmo theme to the latest patched version immediately
• If no patch is available, consider temporarily disabling the theme and switching to a secure alternative
• Review web server and application logs for evidence of exploitation attempts
• Implement WAF rules to block path traversal attack patterns while awaiting a patch

Patch Information

Users should check for updated versions of the Rhythmo theme from ThemeREX. Detailed vulnerability information and patch status can be found in the Patchstack WordPress Vulnerability Report.

Workarounds

• Implement server-level open_basedir restrictions to limit PHP file access to the WordPress directory
• Configure ModSecurity or similar WAF with rules to block path traversal sequences
• Add custom .htaccess rules to block requests containing suspicious path patterns
• Consider using a WordPress security plugin that provides virtual patching capabilities

# Example .htaccess rules to block path traversal attempts
<IfModule mod_rewrite.c>
    RewriteEngine On
    RewriteCond %{QUERY_STRING} (\.\./|\.\.\\) [NC,OR]
    RewriteCond %{QUERY_STRING} (\.\.%2f|\.\.%5c) [NC,OR]
    RewriteCond %{QUERY_STRING} (\.\.%252f|\.\.%255c) [NC]
    RewriteRule .* - [F,L]
</IfModule>