📄 Description (English)
zFTP Client 20061220+dfsg3-4.1 contains a buffer overflow vulnerability in the NAME parameter handling of FTP connections that allows local attackers to crash the application or execute arbitrary code. Attackers can supply an oversized NAME value exceeding the 80-byte buffer allocated in strcpy_chk to overwrite the instruction pointer and execute shellcode with user privileges.
🤖 AI Executive Summary
CVE-2016-20046 is a critical buffer overflow vulnerability in zFTP Client affecting FTP NAME parameter handling, allowing local attackers to crash the application or execute arbitrary code with user privileges. The vulnerability exploits unsafe strcpy_chk usage with an 80-byte buffer, enabling instruction pointer overwrite and shellcode execution. With a CVSS score of 8.4 and no available patch, this poses significant risk to organizations using legacy FTP clients for file transfer operations.
📄 Description (Arabic)
🤖 AI Intelligence Analysis Analyzed: Apr 24, 2026 06:57
🇸🇦 Saudi Arabia Impact Assessment
Saudi organizations in banking (SAMA-regulated institutions), government agencies (NCA oversight), and energy sector (ARAMCO, oil & gas operations) utilizing legacy FTP clients for secure file transfers face significant risk. Telecommunications providers (STC, Mobily) managing network infrastructure and healthcare institutions (MOH) handling patient data transfers are particularly vulnerable. Local privilege escalation could compromise sensitive financial data, government communications, operational technology systems, and patient information. The lack of available patches makes this a persistent threat requiring immediate mitigation.
🏢 Affected Saudi Sectors
Banking and Financial Services
Government and Public Administration
Energy and Oil & Gas
Telecommunications
Healthcare
Defense and Security
Transportation and Logistics
🎯 MITRE ATT&CK Techniques
⚖️ Saudi Risk Score (AI)
8.2
/ 10.0
🔧 Remediation Steps (English)
Immediate Actions:
1. Inventory all systems running zFTP Client 20061220+dfsg3-4.1 and document usage patterns
2. Restrict local access to systems running zFTP Client through access controls and privilege management
3. Disable FTP services where possible and migrate to SFTP/FTPS alternatives
4. Implement application whitelisting to prevent unauthorized code execution
Compensating Controls:
1. Deploy host-based intrusion detection (HIDS) with rules monitoring for buffer overflow attempts and abnormal process behavior
2. Enable Address Space Layout Randomization (ASLR) and Data Execution Prevention (DEP) on affected systems
3. Run zFTP Client in sandboxed/containerized environments with minimal privileges
4. Monitor system logs for segmentation faults and unauthorized code execution attempts
5. Implement strict input validation at network boundaries for FTP traffic
Long-term Remediation:
1. Replace zFTP Client with modern, actively maintained FTP alternatives (FileZilla, WinSCP, or native SFTP clients)
2. Migrate all FTP operations to SFTP (SSH File Transfer Protocol) or FTPS (FTP over SSL/TLS)
3. Conduct security code review of any custom FTP implementations
4. Establish patch management policy requiring immediate replacement of unsupported software
Detection Rules:
1. Monitor for processes spawning from zFTP Client with unexpected parent-child relationships
2. Alert on segmentation faults (SIGSEGV) from zFTP Client processes
3. Track FTP NAME parameters exceeding 80 bytes in network traffic
4. Monitor for code execution attempts from user home directories where FTP clients typically run
🔧 خطوات المعالجة (العربية)
الإجراءات الفورية:
1. حصر جميع الأنظمة التي تقوم بتشغيل zFTP Client 20061220+dfsg3-4.1 وتوثيق أنماط الاستخدام
2. تقييد الوصول المحلي للأنظمة التي تقوم بتشغيل zFTP Client من خلال عناصر التحكم في الوصول وإدارة الامتيازات
3. تعطيل خدمات FTP حيث أمكن والهجرة إلى بدائل SFTP/FTPS
4. تنفيذ قائمة بيضاء للتطبيقات لمنع تنفيذ الكود غير المصرح به
عناصر التحكم التعويضية:
1. نشر كشف التطفل على مستوى المضيف (HIDS) مع قواعد مراقبة محاولات تجاوز المخزن المؤقت والسلوك غير الطبيعي للعملية
2. تفعيل Address Space Layout Randomization (ASLR) و Data Execution Prevention (DEP) على الأنظمة المتأثرة
3. تشغيل zFTP Client في بيئات معزولة/محتوية مع امتيازات محدودة
4. مراقبة سجلات النظام لأخطاء التجزئة ومحاولات تنفيذ الكود غير المصرح به
5. تنفيذ التحقق الصارم من المدخلات على حدود الشبكة لحركة FTP
العلاج طويل الأجل:
1. استبدال zFTP Client بدائل FTP حديثة وتحت الصيانة النشطة (FileZilla أو WinSCP أو عملاء SFTP الأصليين)
2. الهجرة من جميع عمليات FTP إلى SFTP (SSH File Transfer Protocol) أو FTPS (FTP عبر SSL/TLS)
3. إجراء مراجعة أمان الكود لأي تطبيقات FTP مخصصة
4. وضع سياسة إدارة التصحيحات التي تتطلب الاستبدال الفوري للبرامج غير المدعومة
قواعد الكشف:
1. مراقبة العمليات التي تنبثق من zFTP Client مع علاقات الوالد والطفل غير المتوقعة
2. التنبيه على أخطاء التجزئة (SIGSEGV) من عمليات zFTP Client
3. تتبع معاملات FTP NAME التي تتجاوز 80 بايت في حركة الشبكة
4. مراقبة محاولات تنفيذ الكود من دلائل المنزل للمستخدم حيث يتم تشغيل عملاء FTP عادة
📋 Regulatory Compliance Mapping
🟢 NCA ECC 2024
ECC 2024 A.5.1.1 - Information security policies and procedures
ECC 2024 A.8.1.1 - User endpoint devices security
ECC 2024 A.8.2.1 - Privileged access management
ECC 2024 A.8.3.1 - Access control implementation
ECC 2024 A.12.2.1 - Change management procedures
ECC 2024 A.12.6.1 - Management of technical vulnerabilities
🔵 SAMA CSF
SAMA CSF ID.BE-1 - Asset management and inventory
SAMA CSF PR.AC-1 - Access control policy and procedures
SAMA CSF PR.DS-6 - Data security and encryption
SAMA CSF DE.CM-1 - Detection and analysis
SAMA CSF RS.MI-1 - Incident response and recovery
🟡 ISO 27001:2022
ISO 27001:2022 A.5.1 - Policies for information security
ISO 27001:2022 A.8.1 - User endpoint device security
ISO 27001:2022 A.8.2 - Privileged access rights
ISO 27001:2022 A.12.2 - Change management
ISO 27001:2022 A.12.6 - Management of technical vulnerabilities
ISO 27001:2022 A.14.2 - Development security
🟣 PCI DSS v4.0.1
PCI DSS 6.2 - Security patches and updates
PCI DSS 6.5.1 - Injection flaws prevention
PCI DSS 11.2 - Vulnerability scanning