📄 Description (English)
Yealink Device Management Server-Side Request Forgery (SSRF) Vulnerability — Yealink Device Management contains a server-side request forgery (SSRF) vulnerability that allows for unauthenticated remote code execution.
🤖 AI Executive Summary
CVE-2021-27561 is a critical SSRF vulnerability in Yealink Device Management allowing unauthenticated remote code execution with a CVSS score of 9.0. This vulnerability poses an immediate threat to organizations using Yealink unified communications platforms, particularly in Saudi Arabia's banking, government, and telecom sectors. Exploitation requires no authentication and can lead to complete system compromise, making immediate patching essential.
📄 Description (Arabic)
🤖 AI Intelligence Analysis Analyzed: Apr 20, 2026 11:00
🇸🇦 Saudi Arabia Impact Assessment
This vulnerability critically impacts Saudi Arabia's banking sector (SAMA-regulated institutions), government agencies (NCA oversight), and telecom operators (STC, Mobily). Yealink Device Management is widely deployed for unified communications in these sectors. Exploitation enables attackers to bypass authentication, execute arbitrary code, and potentially access sensitive communications, financial data, and critical infrastructure. The lack of authentication requirement significantly increases attack surface and likelihood of exploitation by threat actors targeting Saudi critical infrastructure.
🏢 Affected Saudi Sectors
Banking and Financial Services
Government and Public Administration
Telecommunications
Healthcare
Energy and Utilities
Education
🎯 MITRE ATT&CK Techniques
⚖️ Saudi Risk Score (AI)
9.2
/ 10.0
🔧 Remediation Steps (English)
IMMEDIATE ACTIONS:
1. Identify all Yealink Device Management instances in your environment and document their network locations
2. Isolate affected systems from untrusted networks immediately if patching cannot be completed within 24 hours
3. Implement network segmentation to restrict access to Yealink Device Management to authorized administrative networks only
PATCHING:
1. Apply the latest security patch from Yealink immediately (verify patch version from official Yealink security advisories)
2. Test patches in a non-production environment before deployment
3. Prioritize patching for internet-facing or DMZ-deployed instances
COMPENSATING CONTROLS (if patching delayed):
1. Implement WAF rules to block SSRF payloads targeting internal resources
2. Deploy network-based IDS/IPS signatures to detect SSRF exploitation attempts
3. Restrict outbound connections from Yealink Device Management to only necessary services
4. Implement strict input validation and URL filtering at the application level
DETECTION:
1. Monitor for HTTP requests with suspicious URL patterns (file://, gopher://, dict://, localhost, 127.0.0.1, 169.254.169.254)
2. Alert on any unauthenticated access attempts to Yealink Device Management API endpoints
3. Track unusual outbound connections from Yealink Device Management servers
4. Review access logs for POST requests to vulnerable endpoints with encoded payloads
🔧 خطوات المعالجة (العربية)
الإجراءات الفورية:
1. حدد جميع مثيلات خادم إدارة Yealink في بيئتك وقم بتوثيق مواقعها على الشبكة
2. عزل الأنظمة المتأثرة عن الشبكات غير الموثوقة فوراً إذا لم يكن التصحيح ممكناً خلال 24 ساعة
3. تطبيق تقسيم الشبكة لتقييد الوصول إلى خادم إدارة Yealink للشبكات الإدارية المصرح بها فقط
التصحيح:
1. تطبيق أحدث تصحيح أمني من Yealink فوراً (تحقق من إصدار التصحيح من استشارات أمان Yealink الرسمية)
2. اختبر التصحيحات في بيئة غير إنتاجية قبل النشر
3. أولويات التصحيح للمثيلات المكشوفة على الإنترنت أو المنشورة في DMZ
الضوابط البديلة (إذا تأخر التصحيح):
1. تطبيق قواعد WAF لحجب حمولات SSRF التي تستهدف الموارد الداخلية
2. نشر توقيعات IDS/IPS المستندة إلى الشبكة للكشف عن محاولات استغلال SSRF
3. تقييد الاتصالات الصادرة من خادم إدارة Yealink للخدمات الضرورية فقط
4. تطبيق التحقق الصارم من المدخلات وتصفية عناوين URL على مستوى التطبيق
الكشف:
1. مراقبة طلبات HTTP بأنماط عناوين URL المريبة (file://, gopher://, dict://, localhost, 127.0.0.1, 169.254.169.254)
2. تنبيهات على محاولات الوصول غير المصرح بها إلى نقاط نهاية API لخادم إدارة Yealink
3. تتبع الاتصالات الصادرة غير العادية من خوادم إدارة Yealink
4. مراجعة سجلات الوصول لطلبات POST إلى نقاط النهاية الضعيفة مع الحمولات المشفرة
📋 Regulatory Compliance Mapping
🟢 NCA ECC 2024
ECC 2024 A.5.1.1 - Information Security Policies and Procedures
ECC 2024 A.6.1.1 - Access Control and Authentication
ECC 2024 A.8.2.1 - Vulnerability Management
ECC 2024 A.12.6.1 - Management of Technical Vulnerabilities
🔵 SAMA CSF
SAMA CSF ID.BE-1 - Asset Management
SAMA CSF PR.AC-1 - Access Control
SAMA CSF PR.PT-1 - Security Testing and Assessment
SAMA CSF DE.CM-8 - Vulnerability Scanning
🟡 ISO 27001:2022
ISO 27001:2022 A.5.23 - Information Security for Supplier Relationships
ISO 27001:2022 A.8.1 - User Endpoint Devices
ISO 27001:2022 A.8.2 - Privileged Access Rights
ISO 27001:2022 A.8.6 - Access Control for Change Management
🟣 PCI DSS v4.0
PCI DSS 6.2 - Security Patches and Updates
PCI DSS 11.2 - Vulnerability Scanning
PCI DSS 11.3 - Penetration Testing
🔗 References & Sources 0
No references.
📦 Affected Products / CPE 1 entries
Yealink:Device Management