📄 Description (English)
Envoy is a high-performance edge/middle/service proxy. Prior to 1.37.1, 1.36.5, 1.35.8, and 1.34.13, the Envoy RBAC (Role-Based Access Control) filter contains a logic vulnerability in how it validates HTTP headers when multiple values are present for the same header name. Instead of validating each header value individually, Envoy concatenates all values into a single comma-separated string. This behavior allows attackers to bypass RBAC policies—specifically "Deny" rules—by sending duplicate headers, effectively obscuring the malicious value from exact-match mechanisms. This vulnerability is fixed in 1.37.1, 1.36.5, 1.35.8, and 1.34.13.
🤖 AI Executive Summary
CVE-2026-26308 is a critical RBAC bypass vulnerability in Envoy proxy versions prior to 1.37.1, 1.36.5, 1.35.8, and 1.34.13. Attackers can bypass 'Deny' access control rules by sending duplicate HTTP headers, causing Envoy to concatenate values instead of validating them individually. With a CVSS score of 7.5 and active exploits available, this poses an immediate threat to organizations using Envoy as an API gateway or service mesh component. Immediate patching is essential for all affected deployments.
📄 Description (Arabic)
🤖 AI Intelligence Analysis Analyzed: May 4, 2026 00:18
🇸🇦 Saudi Arabia Impact Assessment
Saudi organizations using Envoy in API gateways, microservices architectures, or service mesh deployments face significant risk. Critical sectors affected include: (1) Banking & Financial Services (SAMA-regulated institutions) relying on Envoy for API security and transaction routing; (2) Government agencies (NCA oversight) using Envoy in digital transformation initiatives; (3) Telecommunications (STC, Mobily) deploying Envoy for network edge security; (4) Energy sector (ARAMCO, utilities) using Envoy in industrial control system integration; (5) Healthcare providers managing patient data through Envoy-protected APIs. The RBAC bypass enables unauthorized access to protected resources, potentially exposing sensitive financial data, government systems, and critical infrastructure.
🏢 Affected Saudi Sectors
Banking & Financial Services
Government & Public Administration
Telecommunications
Energy & Utilities
Healthcare
E-commerce & Retail
Insurance
Education
🎯 MITRE ATT&CK Techniques
⚖️ Saudi Risk Score (AI)
8.2
/ 10.0
🔧 Remediation Steps (English)
IMMEDIATE ACTIONS:
1. Identify all Envoy deployments in your infrastructure using versions <1.34.13, <1.35.8, <1.36.5, or <1.37.1
2. Assess which deployments enforce RBAC policies with 'Deny' rules
3. Implement network segmentation to restrict access to Envoy-protected services
PATCHING GUIDANCE:
1. Upgrade to patched versions: 1.37.1, 1.36.5, 1.35.8, or 1.34.13 immediately
2. Test patches in non-production environments first
3. Plan rolling updates to minimize service disruption
4. Verify RBAC policy enforcement post-upgrade
COMPENSATING CONTROLS (if immediate patching delayed):
1. Implement WAF rules to detect and block duplicate header injection attempts
2. Deploy network-level monitoring to flag suspicious multi-value header patterns
3. Restrict direct access to Envoy admin interface
4. Enable detailed access logging for all RBAC decisions
DETECTION RULES:
1. Monitor for HTTP requests with duplicate header names (e.g., multiple 'Authorization' headers)
2. Alert on RBAC policy violations followed by successful request completion
3. Track requests with comma-separated values in security-critical headers
4. Correlate failed RBAC checks with subsequent successful access to same resource
🔧 خطوات المعالجة (العربية)
الإجراءات الفورية:
1. تحديد جميع نشرات Envoy في البنية التحتية الخاصة بك باستخدام إصدارات <1.34.13 أو <1.35.8 أو <1.36.5 أو <1.37.1
2. تقييم النشرات التي تفرض سياسات RBAC مع قواعد 'الرفض'
3. تنفيذ تقسيم الشبكة لتقييد الوصول إلى الخدمات المحمية بواسطة Envoy
إرشادات الترقية:
1. الترقية إلى الإصدارات المصححة: 1.37.1 أو 1.36.5 أو 1.35.8 أو 1.34.13 فوراً
2. اختبار التصحيحات في بيئات غير الإنتاج أولاً
3. التخطيط للتحديثات المتدرجة لتقليل انقطاع الخدمة
4. التحقق من فرض سياسة RBAC بعد الترقية
الضوابط البديلة (إذا تأخرت الترقية الفورية):
1. تنفيذ قواعد WAF للكشف عن محاولات حقن رؤوس مكررة وحجبها
2. نشر المراقبة على مستوى الشبكة لتحديد أنماط رؤوس متعددة القيم المريبة
3. تقييد الوصول المباشر إلى واجهة إدارة Envoy
4. تفعيل تسجيل الوصول التفصيلي لجميع قرارات RBAC
قواعد الكشف:
1. مراقبة طلبات HTTP برؤوس مكررة (مثل رؤوس 'Authorization' متعددة)
2. التنبيه على انتهاكات سياسة RBAC متبوعة بإكمال الطلب بنجاح
3. تتبع الطلبات ذات القيم المفصولة بفواصل في رؤوس حساسة للأمان
4. ربط فحوصات RBAC الفاشلة مع الوصول الناجح اللاحق إلى نفس المورد
📋 Regulatory Compliance Mapping
🟢 NCA ECC 2024
ECC 2024 A.5.1.1 - Access Control Policy: RBAC bypass violates access control principles
ECC 2024 A.5.1.2 - User Registration and De-registration: Unauthorized access due to RBAC failure
ECC 2024 A.5.2.1 - User Access Management: Failure to properly enforce access restrictions
ECC 2024 A.5.3.1 - Management of Privileged Access Rights: Bypass of privilege enforcement mechanisms
🔵 SAMA CSF
SAMA CSF ID.AC-1 - Access Control: Inadequate validation of access control decisions
SAMA CSF PR.AC-1 - Processes and procedures for access management: RBAC policy enforcement failure
SAMA CSF PR.AC-4 - Access rights and privileges: Bypass of role-based restrictions
SAMA CSF DE.CM-1 - Detection and monitoring of unauthorized access attempts
🟡 ISO 27001:2022
ISO 27001:2022 A.5.3 - Access Control: Failure to enforce access control policies
ISO 27001:2022 A.5.15 - Access Control for Cryptography: Potential exposure of cryptographic keys through unauthorized access
ISO 27001:2022 A.8.3 - Cryptography: Bypass of access controls protecting cryptographic material
ISO 27001:2022 A.8.22 - Information Security Incident Management: Incident response for unauthorized access
🟣 PCI DSS v4.0.1
PCI DSS 3.2.1 - Access Control: Failure to restrict access to cardholder data
PCI DSS 7.1 - Limit access to cardholder data: RBAC bypass enables unauthorized data access
PCI DSS 7.2 - Establish access for users: Inadequate enforcement of user access restrictions
📦 Affected Products / CPE 4 entries
envoyproxy:envoy
envoyproxy:envoy
envoyproxy:envoy
envoyproxy:envoy:1.37.0