📄 Description (English)
The Post Category Gallery plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's 'postcategorygallery' shortcode in versions up to, and including, 1.0.0. This is due to insufficient input sanitization and output escaping on user-supplied shortcode attributes (such as total_width, color_scheme, and caption_font_size) inside the sc_horcatbar() function, which are concatenated directly into HTML attribute values. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.
🤖 AI Executive Summary
The Post Category Gallery WordPress plugin (versions ≤1.0.0) contains a Stored XSS vulnerability in its shortcode handler that allows authenticated contributors to inject malicious scripts through insufficiently sanitized attributes. While requiring contributor-level access, successful exploitation enables persistent script injection affecting all site visitors. This poses a moderate risk to Saudi organizations using WordPress for content management, particularly those with multiple content contributors.
📄 Description (Arabic)
🤖 AI Intelligence Analysis Analyzed: May 28, 2026 11:49
🇸🇦 Saudi Arabia Impact Assessment
Saudi organizations most affected include: (1) Government agencies and municipalities using WordPress for public information portals and citizen services; (2) Educational institutions (universities, schools) managing course content and announcements; (3) Healthcare facilities publishing patient information and medical resources; (4) Media and publishing companies; (5) Small-to-medium enterprises using WordPress for corporate websites. The vulnerability is particularly concerning for organizations with distributed content teams where contributor access is common. Compromised sites could spread malware, harvest credentials, or conduct phishing attacks against Saudi users.
🏢 Affected Saudi Sectors
Government and Public Administration
Education
Healthcare
Media and Publishing
Telecommunications
Retail and E-commerce
Financial Services
Non-Profit Organizations
🎯 MITRE ATT&CK Techniques
⚖️ Saudi Risk Score (AI)
6.2
/ 10.0
🔧 Remediation Steps (English)
IMMEDIATE ACTIONS:
1. Audit all WordPress installations using Post Category Gallery plugin and identify version numbers
2. Review user access logs to identify contributors who may have injected malicious content
3. Scan published pages/posts containing 'postcategorygallery' shortcodes for suspicious attribute values
PATCHING GUIDANCE:
1. Disable the Post Category Gallery plugin immediately until a patched version is available
2. If plugin functionality is critical, contact the plugin developer for security updates
3. Monitor the plugin's repository for version updates addressing CVE-2026-8867
COMPENSATING CONTROLS (if plugin cannot be disabled):
1. Restrict contributor role to trusted personnel only; audit existing contributors
2. Implement Web Application Firewall (WAF) rules to detect/block XSS patterns in shortcode attributes
3. Enable WordPress security plugins (e.g., Wordfence, Sucuri) with XSS detection
4. Implement Content Security Policy (CSP) headers to restrict inline script execution
5. Use WordPress hooks to sanitize shortcode output: add_filter('shortcode_atts_postcategorygallery', 'sanitize_callback')
DETECTION RULES:
1. Monitor database for 'postcategorygallery' shortcodes containing: <script, javascript:, onerror=, onload=, onclick=
2. Log all contributor-level post/page modifications
3. Alert on any changes to posts containing this shortcode
4. Review page source for unexpected inline scripts in rendered HTML
🔧 خطوات المعالجة (العربية)
الإجراءات الفورية:
1. تدقيق جميع تثبيتات WordPress التي تستخدم مكون Post Category Gallery وتحديد أرقام الإصدارات
2. مراجعة سجلات الوصول للمستخدمين لتحديد المساهمين الذين قد يكونون قد حقنوا محتوى ضاراً
3. فحص الصفحات/المنشورات المنشورة التي تحتوي على اختصارات 'postcategorygallery' بحثاً عن قيم سمات مريبة
إرشادات التصحيح:
1. تعطيل مكون Post Category Gallery فوراً حتى يتوفر إصدار معدل
2. إذا كانت وظيفة المكون حرجة، اتصل بمطور المكون للحصول على تحديثات الأمان
3. مراقبة مستودع المكون للحصول على تحديثات الإصدار التي تعالج CVE-2026-8867
الضوابط البديلة (إذا لم يكن من الممكن تعطيل المكون):
1. تقييد دور المساهم للموظفين الموثوقين فقط؛ تدقيق المساهمين الحاليين
2. تنفيذ قواعد جدار حماية تطبيقات الويب (WAF) للكشف عن أنماط XSS وحجبها
3. تفعيل مكونات أمان WordPress (مثل Wordfence و Sucuri) مع كشف XSS
4. تنفيذ رؤوس سياسة أمان المحتوى (CSP) لتقييد تنفيذ البرامج النصية المضمنة
5. استخدام خطافات WordPress لتعقيم مخرجات الاختصار
قواعد الكشف:
1. مراقبة قاعدة البيانات بحثاً عن اختصارات 'postcategorygallery' تحتوي على: <script أو javascript: أو onerror= أو onload= أو onclick=
2. تسجيل جميع تعديلات المنشورات/الصفحات على مستوى المساهم
3. التنبيه على أي تغييرات في المنشورات التي تحتوي على هذا الاختصار
4. مراجعة مصدر الصفحة بحثاً عن برامج نصية مضمنة غير متوقعة في HTML المعروض
📋 Regulatory Compliance Mapping
🟢 NCA ECC 2024
5.1.1 - Input validation and sanitization controls
5.2.1 - Output encoding and escaping requirements
5.3.2 - Web application security controls
6.1.1 - Vulnerability management and patching
🔵 SAMA CSF
ID.SC-7 - Software, firmware, and information integrity
PR.DS-2 - Data-in-transit is protected
PR.IP-1 - System development and acquisition processes
DE.CM-1 - The network is monitored for unauthorized connections
🟡 ISO 27001:2022
A.14.2.1 - Secure development policy
A.14.2.5 - Secure development environment
A.14.3.1 - Separation of development, test and production environments
A.12.6.1 - Management of technical vulnerabilities
🟣 PCI DSS v4.0.1
6.5.1 - Injection flaws (including XSS)
6.5.7 - Cross-site scripting (XSS)
6.2 - Ensure security patches are installed
🔗 References & Sources 3
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https://plugins.trac.wordpress.org/browser/post-category-gallery/trunk/horcatbar.php#L79
security@wordfence.com
https://plugins.trac.wordpress.org/browser/post-category-gallery/trunk/horcatbar.php#L97
security@wordfence.com
https://www.wordfence.com/threat-intel/vulnerabilities/id/f439718e-4a3d-4dc9-a16c-6b655...
security@wordfence.com