📄 Description (English)
When a SIP profile is configured on a virtual server, undisclosed traffic can cause the Traffic Management Microkernel (TMM) to terminate.
Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
🤖 AI Executive Summary
CVE-2026-40423 is a high-severity denial of service vulnerability affecting SIP-configured virtual servers where undisclosed traffic causes the Traffic Management Microkernel (TMM) to crash. With a CVSS score of 7.5 and no patch currently available, this poses immediate operational risk to telecommunications and VoIP infrastructure. The lack of exploit availability provides limited window for remediation before potential weaponization.
📄 Description (Arabic)
🤖 AI Intelligence Analysis Analyzed: May 20, 2026 15:01
🇸🇦 Saudi Arabia Impact Assessment
This vulnerability directly impacts Saudi telecommunications operators (STC, Mobily, Zain) and government VoIP infrastructure managed by NCA. Banking sector VoIP systems and ARAMCO's internal communications networks are at risk. Healthcare facilities using SIP-based telephony systems and government agencies relying on unified communications are vulnerable to service disruption. The TMM crash can cause complete loss of call routing and traffic management, affecting critical communications during emergencies.
🏢 Affected Saudi Sectors
Telecommunications (STC, Mobily, Zain)
Government (NCA, Ministry of Interior)
Banking and Financial Services (SAMA regulated)
Energy (ARAMCO)
Healthcare
Defense and Security
🎯 MITRE ATT&CK Techniques
⚖️ Saudi Risk Score (AI)
7.8
/ 10.0
🔧 Remediation Steps (English)
Immediate Actions:
1. Identify all virtual servers with SIP profiles enabled in your infrastructure
2. Implement network segmentation to restrict SIP traffic sources to trusted endpoints only
3. Enable detailed logging and monitoring of SIP traffic patterns for anomaly detection
4. Establish incident response procedures for TMM crashes
Compensating Controls (until patch available):
5. Deploy SIP traffic rate limiting and validation at network perimeter
6. Implement DDoS mitigation rules specifically for SIP protocol (UDP 5060, TCP 5060, TLS 5061)
7. Configure automatic TMM restart mechanisms with alerting
8. Use network-based SIP inspection to filter malformed packets
9. Maintain redundant SIP infrastructure with failover capabilities
Detection Rules:
10. Monitor for unexpected TMM process termination events
11. Alert on unusual SIP packet patterns or oversized SIP messages
12. Track SIP session establishment failures and rapid connection attempts
13. Monitor system logs for CWE-770 resource exhaustion indicators
Patching:
14. Subscribe to vendor security advisories for patch availability
15. Prepare change management procedures for immediate deployment once patch released
🔧 خطوات المعالجة (العربية)
الإجراءات الفورية:
1. تحديد جميع الخوادم الافتراضية مع ملفات تعريف SIP المفعلة في البنية التحتية
2. تنفيذ تقسيم الشبكة لتقييد مصادر حركة مرور SIP إلى نقاط نهاية موثوقة فقط
3. تفعيل التسجيل والمراقبة التفصيلية لأنماط حركة مرور SIP للكشف عن الشذوذ
4. وضع إجراءات الاستجابة للحوادث لأعطال TMM
الضوابط البديلة (حتى توفر التصحيح):
5. نشر تحديد معدل حركة مرور SIP والتحقق من صحتها على محيط الشبكة
6. تنفيذ قواعد تخفيف DDoS خصيصاً لبروتوكول SIP (UDP 5060، TCP 5060، TLS 5061)
7. تكوين آليات إعادة تشغيل TMM التلقائية مع التنبيهات
8. استخدام فحص SIP القائم على الشبكة لتصفية الحزم المشوهة
9. الحفاظ على بنية تحتية SIP زائدة مع قدرات الفشل
قواعد الكشف:
10. مراقبة أحداث إنهاء عملية TMM غير المتوقعة
11. التنبيه على أنماط حزم SIP غير العادية أو رسائل SIP الكبيرة
12. تتبع فشل إنشاء جلسة SIP ومحاولات الاتصال السريعة
13. مراقبة سجلات النظام لمؤشرات استنزاف الموارد CWE-770
التصحيح:
14. الاشتراك في تنبيهات أمان البائع لتوفر التصحيح
15. تحضير إجراءات إدارة التغيير للنشر الفوري عند توفر التصحيح
📋 Regulatory Compliance Mapping
🟢 NCA ECC 2024
ECC 2024 A.12.6.1 - Management of technical vulnerabilities
ECC 2024 A.12.2.1 - Change management procedures
ECC 2024 A.12.3.1 - Segregation of networks
ECC 2024 A.12.4.1 - Event logging and monitoring
🔵 SAMA CSF
ID.RA-1 - Asset management and vulnerability identification
PR.IP-12 - System and communications protection
DE.CM-1 - Detection and analysis of anomalies
RS.RP-1 - Response planning and procedures
🟡 ISO 27001:2022
A.12.2.1 - Change management
A.12.3.1 - Segregation of networks
A.12.4.1 - Event logging
A.12.6.1 - Management of technical vulnerabilities
A.13.1.3 - Segregation of information systems
🟣 PCI DSS v4.0.1
Requirement 6.2 - Security patches and updates
Requirement 11.2 - Vulnerability scanning
Requirement 12.2 - Configuration standards
🔗 References & Sources 1