CVE-2026-78259: WPLegalPages Authentication Bypass Flaw

CVE-2026-78259 Overview

CVE-2026-78259 is a broken authentication vulnerability affecting the WPLegalPages WordPress plugin in versions up to and including 3.7.0. The flaw allows unauthenticated attackers to bypass authentication controls over the network without user interaction. The weakness maps to [CWE-288: Authentication Bypass Using an Alternate Path or Channel]. Attackers can reach the affected functionality remotely with low attack complexity and no prior privileges, exposing the confidentiality, integrity, and availability of WordPress sites running the plugin.

Critical Impact
Unauthenticated network attackers can bypass authentication in WPLegalPages <= 3.7.0, gaining access to plugin functionality intended to be restricted.

Affected Products

WPLegalPages WordPress plugin versions <= 3.7.0
WordPress sites with the vulnerable plugin installed and activated
Any hosting environment exposing the affected plugin endpoints to the internet

Discovery Timeline

2026-08-24 - CVE-2026-78259 published to NVD
2026-08-26 - Last updated in NVD database

Technical Details for CVE-2026-78259

Vulnerability Analysis

The vulnerability is a broken authentication flaw in the WPLegalPages plugin. It is exploitable over the network without authentication and without user interaction. The Exploit Prediction Scoring System (EPSS) probability is 0.216% with a percentile of 11.846, indicating limited observed exploitation activity at the time of publication. No public proof-of-concept or exploit code is currently referenced in NVD.

Successful exploitation gives attackers access to plugin functions that should require authenticated sessions. Depending on the exposed operation, this can lead to disclosure of configuration data, modification of legal page content displayed to site visitors, or disruption of plugin operations. Because WPLegalPages content typically renders on public-facing pages, tampered output can be used to stage secondary attacks against site visitors.

Root Cause

The root cause is classified under [CWE-288], where the plugin exposes sensitive functionality through an alternate access path that fails to enforce authentication or capability checks. The plugin does not adequately validate the identity or privileges of the caller before executing privileged actions. See the Patchstack advisory for vendor and technical details.

Attack Vector

An attacker sends crafted HTTP requests to the vulnerable plugin endpoints exposed by a WordPress site running WPLegalPages <= 3.7.0. The request bypasses the authentication check and invokes restricted plugin functionality directly. No credentials, tokens, or user interaction are required. The vulnerability manifests in the plugin's handler routing rather than in a specific code path with a public patch diff; refer to the vendor advisory for exact endpoint details.

Detection Methods for CVE-2026-78259

Indicators of Compromise

Unexpected modifications to WordPress pages generated or managed by the WPLegalPages plugin, including privacy policy, terms, or cookie notice pages.
HTTP requests from unauthenticated sources reaching WPLegalPages plugin endpoints under /wp-admin/admin-ajax.php or /wp-json/ with plugin-specific actions.
New or altered plugin option entries in the wp_options table referencing WPLegalPages configuration keys.

Detection Strategies

Inventory WordPress installations and identify sites running WPLegalPages at version 3.7.0 or earlier.
Correlate web server access logs against plugin routes to identify unauthenticated calls to restricted actions.
Monitor WordPress audit logs for administrative changes originating from sessions without a matching authentication event.

Monitoring Recommendations

Enable WordPress security logging plugins to record plugin option changes and administrative actions.
Forward web server and WordPress application logs to a centralized log platform for correlation and long-term retention.
Alert on HTTP 200 responses to WPLegalPages endpoints where the request lacks a valid authenticated session cookie or nonce.

How to Mitigate CVE-2026-78259

Immediate Actions Required

Identify all WordPress sites running WPLegalPages and confirm the installed version.
Update WPLegalPages to a fixed release above 3.7.0 as soon as one is available from the vendor.
Restrict administrative and plugin AJAX/REST endpoints at the web application firewall (WAF) layer until patching completes.

Patch Information

Refer to the Patchstack advisory for WPLegalPages for the authoritative fixed version and remediation guidance. Apply the vendor-supplied update through the WordPress plugin manager or by replacing the plugin files directly.

Workarounds

Deactivate and remove the WPLegalPages plugin from affected WordPress sites until a patched version is installed.
Deploy WAF rules to block unauthenticated requests to WPLegalPages plugin action names and REST routes.
Restrict access to /wp-admin/ and /wp-json/ from untrusted networks using IP allowlisting or authentication proxies.

bash

# Configuration example: block unauthenticated access to the plugin's admin-ajax actions
# Example nginx rule - adjust action names to match vendor advisory
location = /wp-admin/admin-ajax.php {
    if ($arg_action ~* "^wplegalpages_") {
        return 403;
    }
}