CVE-2026-24554: WPSubscription CSRF Vulnerability

CVE-2026-24554 Overview

CVE-2026-24554 is a Cross-Site Request Forgery (CSRF) vulnerability [CWE-352] affecting the Convers Lab WPSubscription plugin for WordPress. The flaw exists in all versions up to and including 1.9.1. An attacker can craft a malicious request that, when triggered by an authenticated user visiting an attacker-controlled page, performs unintended actions within the WPSubscription plugin. The vulnerability requires user interaction and operates over the network without prior authentication on the attacker's side.

Critical Impact
Successful exploitation enables an attacker to perform plugin actions on behalf of an authenticated WordPress user, potentially altering subscription configuration or related plugin state through forged requests.

Affected Products

Convers Lab WPSubscription plugin for WordPress
All versions from n/a through 1.9.1
WordPress sites with WPSubscription installed and active

Discovery Timeline

2026-05-25 - CVE-2026-24554 published to the National Vulnerability Database (NVD)
2026-05-26 - Last updated in NVD database

Technical Details for CVE-2026-24554

Vulnerability Analysis

The WPSubscription plugin exposes state-changing endpoints that do not adequately verify the origin or intent of incoming HTTP requests. The vulnerability is classified as Cross-Site Request Forgery under [CWE-352]. An attacker hosts a crafted page or link containing the request payload. When an authenticated WordPress user, typically a site administrator, visits the page, the browser submits the request with the user's active session cookies. The plugin processes the request as if the user initiated it, because the required anti-CSRF token validation is missing or insufficient.

The EPSS probability for active exploitation remains low at the time of publication, reflecting limited public exploitation activity. However, CSRF flaws in widely deployed WordPress plugins are routinely incorporated into mass-exploitation toolkits.

Root Cause

The root cause is the absence or improper validation of WordPress nonces on plugin actions that modify server-side state. WordPress provides wp_nonce_field() and check_admin_referer() primitives specifically to prevent CSRF, and WPSubscription through version 1.9.1 does not enforce these checks consistently on all state-changing handlers.

Attack Vector

The attack proceeds over the network and requires user interaction. An attacker prepares an HTML page containing a hidden form or image tag that issues a request to the vulnerable WPSubscription endpoint on the target site. The attacker then lures an authenticated WordPress administrator to that page through phishing, a forum post, or a malicious advertisement. The victim's browser submits the request with valid authentication cookies, and the plugin executes the requested action. No exploit code or proof-of-concept is publicly available at this time. See the Patchstack WordPress Vulnerability Report for additional technical context.

Detection Methods for CVE-2026-24554

Indicators of Compromise

Unexpected changes to WPSubscription plugin settings or subscription records without corresponding admin login activity
HTTP POST requests to WPSubscription endpoints with Referer headers pointing to external, untrusted domains
Administrator session activity originating from pages outside the WordPress admin interface

Detection Strategies

Review WordPress audit logs for plugin configuration changes that lack a corresponding authenticated admin page visit
Inspect web server access logs for requests to WPSubscription action handlers missing valid _wpnonce parameters
Correlate browser referer data with the timing of plugin state changes to identify cross-origin request patterns

Monitoring Recommendations

Deploy a web application firewall (WAF) rule that requires a valid same-origin Referer or Origin header for WPSubscription state-changing requests
Enable WordPress activity logging plugins to capture plugin setting modifications with user, IP, and referer context
Alert on administrator actions performed without a preceding wp-admin page load in the same session

How to Mitigate CVE-2026-24554

Immediate Actions Required

Update the WPSubscription plugin to a version later than 1.9.1 once a vendor patch is published
Audit recent WPSubscription configuration changes to identify any unauthorized modifications
Restrict administrator browsing habits and require dedicated browsers or sessions for WordPress admin work

Patch Information

No fixed version is listed in the NVD entry at the time of publication. Site operators should monitor the Patchstack advisory and the official WordPress plugin repository for an updated release addressing CVE-2026-24554.

Workarounds

Deactivate the WPSubscription plugin until a patched version is available if subscription functionality is not business-critical
Configure a WAF to block requests to WPSubscription endpoints lacking same-origin Referer and Origin headers
Enforce SameSite=Strict or SameSite=Lax cookie attributes on WordPress authentication cookies to limit cross-site cookie transmission

bash

# Example Nginx rule to block cross-origin POSTs to the plugin
location ~* /wp-content/plugins/subscription/ {
    if ($request_method = POST) {
        set $block 1;
    }
    if ($http_origin ~* ^https?://(www\.)?example\.com$) {
        set $block 0;
    }
    if ($block = 1) {
        return 403;
    }
}