📄 Description (English)
Apache Flink Improper Access Control Vulnerability — Apache Flink contains an improper access control vulnerability that allows an attacker to read any file on the local filesystem of the JobManager through its REST interface.
🤖 AI Executive Summary
CVE-2020-17519 is a critical improper access control vulnerability in Apache Flink (CVSS 9.0) that allows unauthenticated attackers to read arbitrary files from the JobManager's local filesystem via the REST API. This path traversal-style attack can expose sensitive configuration files, credentials, private keys, and application secrets without requiring authentication. A public exploit is available, making this vulnerability actively exploitable in the wild. Organizations running Apache Flink for big data and stream processing workloads must patch immediately.
📄 Description (Arabic)
🤖 AI Intelligence Analysis Analyzed: Apr 18, 2026 21:31
🇸🇦 Saudi Arabia Impact Assessment
Saudi organizations leveraging big data analytics and real-time stream processing are at significant risk. Key sectors include: Energy (Saudi Aramco, NEOM smart infrastructure using Flink for IoT/telemetry data pipelines), Telecom (STC, Mobily using Flink for real-time network analytics), Banking/Finance (SAMA-regulated institutions using Flink for fraud detection and transaction monitoring), and Government (Vision 2030 digital transformation projects with data lake architectures). Exploitation could expose database credentials, cloud provider keys (AWS/Azure), LDAP configurations, and internal network topology details stored in Flink configuration files, potentially enabling lateral movement across enterprise environments.
🏢 Affected Saudi Sectors
Energy
Banking
Government
Telecom
Healthcare
Smart Cities
Retail
🎯 MITRE ATT&CK Techniques
⚖️ Saudi Risk Score (AI)
9.2
/ 10.0
🔧 Remediation Steps (English)
IMMEDIATE ACTIONS:
1. Identify all Apache Flink deployments across your environment using asset inventory tools
2. Isolate JobManager REST interfaces (default port 8081) from public internet access immediately
3. Apply network-level ACLs to restrict REST API access to trusted IP ranges only
PATCHING GUIDANCE:
4. Upgrade Apache Flink to version 1.11.3 or 1.12.0 or later which contain the fix
5. Verify patch integrity using official Apache checksums before deployment
6. Restart all Flink cluster components after patching
COMPENSATING CONTROLS (if patching is delayed):
7. Deploy a reverse proxy (nginx/HAProxy) in front of JobManager REST API with authentication enforcement
8. Implement Web Application Firewall (WAF) rules to block path traversal patterns (../, %2e%2e, etc.)
9. Run Flink JobManager in a containerized environment with read-only filesystem mounts where possible
10. Restrict Flink process user permissions to minimum required directories
DETECTION RULES:
11. Monitor REST API logs for requests containing traversal patterns: GET /jobmanager/logs/../
12. Create SIEM alerts for HTTP 200 responses to paths containing '../' or encoded equivalents
13. Deploy Snort/Suricata rule: alert tcp any any -> $FLINK_SERVERS 8081 (msg:"CVE-2020-17519 Path Traversal"; content:"GET"; content:".."; sid:2020175190;)
14. Monitor for access to sensitive files: /etc/passwd, flink-conf.yaml, log4j.properties
15. Review Flink JobManager access logs for anomalous file read patterns
🔧 خطوات المعالجة (العربية)
الإجراءات الفورية:
1. تحديد جميع نشرات Apache Flink عبر البيئة باستخدام أدوات جرد الأصول
2. عزل واجهات REST الخاصة بـ JobManager (المنفذ الافتراضي 8081) عن الإنترنت العام فوراً
3. تطبيق قوائم التحكم بالوصول على مستوى الشبكة لتقييد الوصول إلى REST API على نطاقات IP موثوقة فقط
إرشادات التصحيح:
4. الترقية إلى Apache Flink الإصدار 1.11.3 أو 1.12.0 أو أحدث التي تحتوي على الإصلاح
5. التحقق من سلامة التصحيح باستخدام مجاميع التحقق الرسمية من Apache قبل النشر
6. إعادة تشغيل جميع مكونات مجموعة Flink بعد التصحيح
ضوابط التعويض (في حال تأخر التصحيح):
7. نشر وكيل عكسي (nginx/HAProxy) أمام REST API الخاص بـ JobManager مع فرض المصادقة
8. تطبيق قواعد جدار حماية تطبيقات الويب (WAF) لحجب أنماط اجتياز المسار
9. تشغيل Flink JobManager في بيئة حاويات مع تحميل نظام ملفات للقراءة فقط
10. تقييد صلاحيات مستخدم عملية Flink على الحد الأدنى المطلوب
قواعد الكشف:
11. مراقبة سجلات REST API للطلبات التي تحتوي على أنماط الاجتياز
12. إنشاء تنبيهات SIEM لاستجابات HTTP 200 للمسارات التي تحتوي على '../'
13. نشر قواعد Snort/Suricata للكشف عن محاولات الاستغلال
14. مراقبة الوصول إلى الملفات الحساسة مثل /etc/passwd وملفات إعداد Flink
15. مراجعة سجلات وصول JobManager بحثاً عن أنماط قراءة ملفات غير طبيعية
📋 Regulatory Compliance Mapping
🟢 NCA ECC 2024
ECC-1-4-2: Access Control — Improper access control to critical system interfaces
ECC-2-3-1: Network Security — Exposure of management interfaces to untrusted networks
ECC-2-5-1: Vulnerability Management — Critical vulnerability patching within defined SLA
ECC-1-3-2: Asset Management — Identification and protection of data processing assets
ECC-2-6-1: Security Monitoring — Detection of unauthorized access attempts
🔵 SAMA CSF
3.3.4 Access Control Management — Unauthorized access to sensitive data via REST API
3.3.6 Vulnerability Management — Critical patch application and compensating controls
3.3.9 Network Security Management — Exposure of internal services to untrusted networks
3.3.14 Cyber Security Incident Management — Detection and response to active exploitation
3.3.2 Information Asset Management — Protection of data processing infrastructure
🟡 ISO 27001:2022
A.9.4.1 — Information access restriction: Unauthenticated access to file system
A.9.4.2 — Secure log-on procedures: Missing authentication on REST interface
A.12.6.1 — Management of technical vulnerabilities: Unpatched critical vulnerability
A.13.1.3 — Segregation in networks: JobManager exposed without network segmentation
A.14.2.5 — Secure system engineering principles: Insecure default configuration
🟣 PCI DSS v4.0
Requirement 6.3.3 — All system components protected from known vulnerabilities via patching
Requirement 7.2 — Access control systems restrict access to cardholder data environment
Requirement 1.3.2 — Restrict inbound traffic to only necessary communications
Requirement 10.7 — Detect and respond to failures of critical security controls
🔗 References & Sources 0
No references.
📦 Affected Products / CPE 1 entries
Apache:Flink