📄 Description (English)
Nebula is a scalable overlay networking tool. In versions from 1.7.0 to 1.10.2, when using P256 certificates (which is not the default configuration), it is possible to evade a blocklist entry created against the fingerprint of a certificate by using ECDSA Signature Malleability to use a copy of the certificate with a different fingerprint. This issue has been patched in version 1.10.3.
🤖 AI Executive Summary
Nebula versions 1.7.0-1.10.2 contain a cryptographic vulnerability allowing attackers to bypass certificate blocklists through ECDSA signature malleability when P256 certificates are used. This enables threat actors to evade security controls and potentially gain unauthorized network access. The vulnerability is patched in version 1.10.3 and requires immediate attention for organizations using Nebula in overlay networking infrastructure.
📄 Description (Arabic)
🤖 AI Intelligence Analysis Analyzed: Apr 26, 2026 09:00
🇸🇦 Saudi Arabia Impact Assessment
This vulnerability primarily impacts Saudi organizations using Nebula for overlay networking, particularly in: (1) Government agencies and NCA infrastructure relying on Nebula for secure inter-agency communications; (2) Banking sector (SAMA-regulated institutions) using Nebula for secure network segmentation and branch connectivity; (3) Telecommunications providers (STC, Mobily, Zain) deploying Nebula for VPN and network overlay services; (4) Energy sector (ARAMCO, SEC) utilizing Nebula for critical infrastructure network isolation. The ability to bypass certificate blocklists directly undermines network access control policies and could enable lateral movement in segmented networks.
🏢 Affected Saudi Sectors
Government
Banking
Telecommunications
Energy
Healthcare
Critical Infrastructure
🎯 MITRE ATT&CK Techniques
⚖️ Saudi Risk Score (AI)
7.8
/ 10.0
🔧 Remediation Steps (English)
Immediate Actions:
1. Identify all Nebula deployments in your environment and document which versions are running
2. Determine if P256 certificates are in use (check Nebula configuration files for certificate specifications)
3. If P256 certificates are NOT in use, risk is significantly lower but patching is still recommended
Patching Guidance:
1. Upgrade all affected Nebula instances to version 1.10.3 or later immediately
2. Plan upgrades during maintenance windows to minimize network disruption
3. Test upgrades in non-production environments first
4. Verify certificate functionality post-upgrade
Compensating Controls (if immediate patching not possible):
1. Implement network-level access controls independent of Nebula certificate validation
2. Deploy additional authentication mechanisms (multi-factor authentication) for network access
3. Monitor and log all certificate-based authentication attempts
4. Restrict Nebula overlay network access to trusted IP ranges only
5. Implement certificate pinning at application level where possible
Detection Rules:
1. Monitor for multiple authentication attempts using different certificate fingerprints from same source IP
2. Alert on certificate validation failures followed by successful connections
3. Track certificate fingerprint changes for known hosts
4. Log and analyze ECDSA signature validation anomalies in Nebula logs
🔧 خطوات المعالجة (العربية)
الإجراءات الفورية:
1. حدد جميع نشرات Nebula في بيئتك وقثق الإصدارات التي تعمل
2. حدد ما إذا كانت شهادات P256 قيد الاستخدام (تحقق من ملفات تكوين Nebula)
3. إذا لم تكن شهادات P256 قيد الاستخدام، فإن المخاطر أقل لكن التصحيح لا يزال موصى به
إرشادات التصحيح:
1. قم بترقية جميع نسخ Nebula المتأثرة إلى الإصدار 1.10.3 أو أحدث فوراً
2. خطط للترقيات خلال نوافذ الصيانة لتقليل انقطاع الشبكة
3. اختبر الترقيات في بيئات غير الإنتاج أولاً
4. تحقق من وظائف الشهادة بعد الترقية
الضوابط البديلة (إذا لم يكن التصحيح الفوري ممكناً):
1. تطبيق ضوابط الوصول على مستوى الشبكة بشكل مستقل عن التحقق من شهادة Nebula
2. نشر آليات مصادقة إضافية (المصادقة متعددة العوامل) لوصول الشبكة
3. مراقبة وتسجيل جميع محاولات المصادقة القائمة على الشهادات
4. تقييد وصول شبكة Nebula المتراكبة إلى نطاقات IP الموثوقة فقط
5. تطبيق تثبيت الشهادات على مستوى التطبيق حيث أمكن
قواعد الكشف:
1. مراقبة محاولات المصادقة المتعددة باستخدام بصمات شهادات مختلفة من نفس عنوان IP
2. تنبيهات عند فشل التحقق من الشهادة متبوعة بالاتصالات الناجحة
3. تتبع تغييرات بصمة الشهادة للمضيفين المعروفين
4. تسجيل وتحليل شذوذ التحقق من توقيع ECDSA في سجلات Nebula
📋 Regulatory Compliance Mapping
🟢 NCA ECC 2024
ECC 2024 - 4.1.1 Access Control Policy
ECC 2024 - 4.2.2 Authentication and Authorization
ECC 2024 - 5.1.1 Cryptographic Controls
ECC 2024 - 5.2.1 Certificate Management
🔵 SAMA CSF
SAMA CSF - ID.AM-2 Software Inventory
SAMA CSF - PR.AC-1 Access Control Policy
SAMA CSF - PR.DS-2 Data-in-Transit Protection
SAMA CSF - DE.CM-1 Network Monitoring
🟡 ISO 27001:2022
ISO 27001:2022 - A.5.15 Access Control
ISO 27001:2022 - A.8.24 Cryptography
ISO 27001:2022 - A.8.25 Cryptographic Key Management
ISO 27001:2022 - A.8.32 Change Management
🟣 PCI DSS v4.0.1
PCI DSS 4.1 - Strong Cryptography
PCI DSS 6.2 - Security Patches
PCI DSS 7.1 - Access Control Implementation
📦 Affected Products / CPE 1 entries
slack:nebula