CVE-2026-28007: Coinpress PHP File Inclusion Vulnerability

CVE-2026-28007 Overview

CVE-2026-28007 is a Local File Inclusion (LFI) vulnerability affecting the ThemeREX Coinpress WordPress theme. This vulnerability stems from improper control of filename parameters in PHP include/require statements, allowing attackers to include arbitrary local files from the server. When exploited, this can lead to sensitive information disclosure, configuration file exposure, and potentially remote code execution if combined with other attack vectors such as log poisoning.

Critical Impact

Unauthenticated attackers may exploit this LFI vulnerability to read sensitive server files, access WordPress configuration credentials, or escalate to remote code execution through file upload chains or log poisoning techniques.

Affected Products

• ThemeREX Coinpress WordPress Theme versions through 1.0.14
• WordPress installations using the vulnerable Coinpress theme
• Web servers hosting affected WordPress deployments

Discovery Timeline

• 2026-03-05 - CVE-2026-28007 published to NVD
• 2026-03-05 - Last updated in NVD database

Technical Details for CVE-2026-28007

Vulnerability Analysis

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

The attack can be performed over the network without requiring authentication or user interaction, though exploitation requires some level of complexity to successfully traverse to sensitive files. Successful exploitation can result in complete compromise of confidentiality, integrity, and availability of the affected system.

Root Cause

The root cause of this vulnerability lies in insufficient input validation and sanitization of user-supplied data that is subsequently used in file inclusion operations. The Coinpress theme accepts filename or path parameters from user requests and directly incorporates them into PHP include/require statements without proper filtering of directory traversal sequences (such as ../) or validation against an allowlist of permitted files.

Attack Vector

The vulnerability is exploitable via network requests targeting the affected WordPress theme endpoints. An attacker crafts malicious HTTP requests containing path traversal sequences in parameters that control file inclusion. By manipulating these parameters with sequences like ../../../etc/passwd or ../../../wp-config.php, attackers can include files outside the intended directory scope.

Successful exploitation typically involves:

1. Identifying vulnerable theme endpoints that accept file parameters
2. Crafting requests with directory traversal sequences to reach sensitive files
3. Reading the contents of configuration files, system files, or other sensitive data
4. Potentially escalating to code execution via log poisoning or chaining with upload vulnerabilities

For technical details on the vulnerability mechanism and affected code paths, refer to the Patchstack Vulnerability Report.

Detection Methods for CVE-2026-28007

Indicators of Compromise

• HTTP requests containing directory traversal sequences (../, ..%2f, %2e%2e/) targeting Coinpress theme endpoints
• Access attempts to sensitive files such as /etc/passwd, wp-config.php, or .htaccess through theme parameters
• Unusual web server log entries showing file path manipulation in request parameters
• Error messages or responses containing contents of system or configuration files

Detection Strategies

• Deploy web application firewall (WAF) rules to detect and block directory traversal patterns in request parameters
• Enable and monitor PHP error logging for include/require failures indicating attempted path traversal
• Implement file integrity monitoring on sensitive configuration files
• Configure intrusion detection systems (IDS) to alert on LFI attack signatures

Monitoring Recommendations

• Review web server access logs for requests containing encoded or plain directory traversal sequences
• Monitor for unusual file access patterns on the web server, particularly reads of configuration files
• Set up alerting for WordPress theme-related endpoints receiving suspicious path parameters
• Track authentication logs for potential credential abuse following information disclosure

How to Mitigate CVE-2026-28007

Immediate Actions Required

• Update the Coinpress WordPress theme to a patched version if available from ThemeREX
• If no patch is available, consider temporarily deactivating the Coinpress theme and switching to a secure alternative
• Implement WAF rules to block directory traversal attempts targeting WordPress theme endpoints
• Restrict file permissions on sensitive configuration files to limit impact of successful exploitation

Patch Information

Consult the Patchstack Vulnerability Report for the latest patch status and remediation guidance from ThemeREX. Organizations should check for theme updates through the WordPress admin dashboard or the vendor's official website.

Workarounds

• Deploy a web application firewall with rules blocking path traversal sequences (../, encoded variants)
• Use PHP's open_basedir directive to restrict file inclusion to specific directories
• Disable the vulnerable theme and use an alternative until a patch is released
• Implement additional server-level access controls to limit file read permissions for the web server process

# Configuration example - Add to .htaccess to block common LFI patterns
RewriteEngine On
RewriteCond %{QUERY_STRING} (\.\./|\.\.) [NC,OR]
RewriteCond %{QUERY_STRING} (\.\.%2f|%2e%2e) [NC]
RewriteRule .* - [F,L]

# PHP open_basedir restriction in php.ini or .htaccess
# php_admin_value open_basedir /var/www/html:/tmp