CVE-2026-57789: Aqua Theme PHP File Inclusion Vulnerability

CVE-2026-57789 Overview

CVE-2026-57789 is a PHP Local File Inclusion (LFI) vulnerability affecting the jwsthemes Aqua WordPress theme through version 5.1.2. The flaw stems from improper control of filenames passed to PHP include or require statements, classified under [CWE-98]. Authenticated attackers with low privileges can coerce the application into loading arbitrary PHP files from the local filesystem. Successful exploitation allows adversaries to execute unintended code, disclose sensitive files, and pivot toward full site compromise. The vulnerability affects all Aqua theme versions up to and including 5.1.2.

Critical Impact
An authenticated attacker can include and execute arbitrary local PHP files, leading to information disclosure, code execution, and potential full compromise of the WordPress site.

Affected Products

jwsthemes Aqua WordPress Theme versions up to and including 5.1.2
WordPress installations using the vulnerable Aqua theme
Any hosting environment running the affected theme in production or staging

Discovery Timeline

2026-07-13 - CVE CVE-2026-57789 published to NVD
2026-07-13 - Last updated in NVD database

Technical Details for CVE-2026-57789

Vulnerability Analysis

The vulnerability resides in how the Aqua theme handles user-supplied input passed to PHP file inclusion statements. When the theme constructs a path for include, include_once, require, or require_once without sufficient validation, an attacker can manipulate the parameter to reference arbitrary files on the server. This class of flaw, tracked as [CWE-98], is commonly referred to as PHP Remote File Inclusion but manifests here as Local File Inclusion.

Exploitation requires network access and low-privilege authentication on the WordPress instance. The attack complexity is high, indicating that specific conditions must be met for reliable exploitation. Once triggered, the attacker gains impact across confidentiality, integrity, and availability of the affected site.

Root Cause

The root cause is missing or insufficient sanitization of a filename parameter used in a PHP inclusion statement within the Aqua theme codebase. The theme fails to enforce an allow-list of permitted files or strip directory traversal sequences such as ../ from the input. This permits path manipulation that resolves to attacker-chosen files.

Attack Vector

An authenticated user sends a crafted HTTP request to a vulnerable endpoint exposed by the Aqua theme. The request includes a parameter that is passed directly into a PHP inclusion function. By supplying a path pointing to a local PHP file, log file, or uploaded asset, the attacker forces the server to execute or disclose that file. Attackers frequently combine LFI with log poisoning or writable upload directories to achieve remote code execution. Refer to the Patchstack advisory for additional technical context.

Detection Methods for CVE-2026-57789

Indicators of Compromise

HTTP requests to Aqua theme endpoints containing directory traversal sequences such as ../ or URL-encoded variants like %2e%2e%2f
Web server access logs showing parameters referencing sensitive files such as wp-config.php, /etc/passwd, or PHP session files
Unexpected PHP execution originating from paths outside the theme directory
New or modified PHP files in wp-content/uploads following suspicious requests

Detection Strategies

Inspect WordPress access logs for authenticated requests targeting Aqua theme PHP files with unusual query parameters
Deploy a web application firewall (WAF) rule to flag path traversal patterns and inclusion of non-theme files
Monitor PHP error logs for include() or require() warnings referencing unexpected paths
Correlate low-privilege user activity with file access anomalies on the web server

Monitoring Recommendations

Enable file integrity monitoring on the WordPress installation directory, especially wp-content/themes/aqua
Alert on any process spawned by the web server user that reads sensitive system files
Track authenticated session activity for accounts issuing requests to theme-level PHP endpoints
Retain HTTP request bodies and query strings for retrospective hunting once patches are available

How to Mitigate CVE-2026-57789

Immediate Actions Required

Identify all WordPress sites running the jwsthemes Aqua theme and inventory installed versions
Restrict low-privilege account creation and audit existing subscriber and contributor accounts
Deploy WAF rules that block path traversal payloads and file inclusion attempts targeting theme endpoints
Disable the Aqua theme on non-production sites until a vendor-supplied patch is applied

Patch Information

At the time of publication, the vulnerability affects Aqua versions up to and including 5.1.2. Administrators should monitor the Patchstack advisory and jwsthemes vendor channels for a fixed release, then upgrade immediately once available.

Workarounds

Temporarily switch to an unaffected WordPress theme until a patched Aqua release is published
Configure PHP open_basedir to constrain file inclusion to the WordPress installation directory
Set allow_url_include=Off and allow_url_fopen=Off in php.ini to reduce inclusion attack surface
Remove or restrict access to Aqua theme PHP files that accept user-controlled path parameters via .htaccess or equivalent server rules

bash

# Configuration example: harden php.ini against file inclusion abuse
allow_url_include = Off
allow_url_fopen = Off
open_basedir = "/var/www/html:/tmp"