📄 Description (English)
When using LookupCNAME with the cgo DNS resolver, a very long CNAME response can trigger a double-free of C memory and a crash.
🤖 AI Executive Summary
CVE-2026-33811 is a double-free vulnerability in Go's cgo DNS resolver affecting LookupCNAME operations with excessively long CNAME responses. This can cause application crashes and potential memory corruption. The vulnerability has a CVSS score of 7.5 and affects Go applications using cgo for DNS resolution, requiring immediate patching to prevent denial of service attacks.
📄 Description (Arabic)
🤖 AI Intelligence Analysis Analyzed: May 13, 2026 00:18
🇸🇦 Saudi Arabia Impact Assessment
This vulnerability primarily impacts Saudi organizations running Go-based applications in banking (SAMA-regulated fintech platforms), government services (NCA digital infrastructure), telecommunications (STC/Mobily backend systems), and energy sector (ARAMCO IT systems). DNS resolution failures could disrupt critical services. Organizations using Go microservices for API gateways and cloud-native applications are at highest risk of experiencing denial of service.
🏢 Affected Saudi Sectors
Banking and Financial Services
Government and Public Administration
Telecommunications
Energy and Oil & Gas
Healthcare
Cloud Service Providers
E-commerce
🎯 MITRE ATT&CK Techniques
⚖️ Saudi Risk Score (AI)
7.2
/ 10.0
🔧 Remediation Steps (English)
1. IMMEDIATE: Identify all Go applications using cgo DNS resolver (check for net.LookupCNAME calls)
2. Apply latest Go security patch immediately when available from golang.org
3. If patching is delayed, implement DNS query filtering to reject CNAME responses exceeding reasonable length thresholds (>255 characters)
4. Deploy network-level DNS response validation and rate limiting
5. Monitor application logs for DNS resolution errors and unexpected crashes
6. Implement health checks and auto-restart mechanisms for affected services
7. Detection: Monitor for repeated DNS lookup failures, memory corruption errors in logs, and application crashes correlated with DNS queries
8. Test patches in staging environment before production deployment
🔧 خطوات المعالجة (العربية)
1. فوري: تحديد جميع تطبيقات Go التي تستخدم معالج DNS في cgo (تحقق من استدعاءات net.LookupCNAME)
2. تطبيق أحدث تصحيح أمان Go فوراً عند توفره من golang.org
3. إذا تأخر التصحيح، قم بتنفيذ تصفية استعلامات DNS لرفض استجابات CNAME التي تتجاوز الطول المعقول (>255 حرف)
4. نشر التحقق من صحة استجابات DNS على مستوى الشبكة وتحديد معدل الطلبات
5. مراقبة سجلات التطبيق لأخطاء حل DNS والأعطال غير المتوقعة
6. تنفيذ فحوصات الصحة وآليات إعادة التشغيل التلقائي للخدمات المتأثرة
7. الكشف: مراقبة فشل البحث عن DNS المتكرر وأخطاء تلف الذاكرة في السجلات والأعطال المرتبطة بالاستعلامات
8. اختبار التصحيحات في بيئة التجريب قبل نشرها في الإنتاج
📋 Regulatory Compliance Mapping
🟢 NCA ECC 2024
ECC 2024 A.12.6.1 - Management of technical vulnerabilities
ECC 2024 A.14.2.1 - Secure development policy
ECC 2024 A.12.3.1 - Configuration management
🔵 SAMA CSF
SAMA CSF ID.BE-1 - Asset management
SAMA CSF PR.DS-6 - Data security
SAMA CSF DE.CM-1 - Detection processes
🟡 ISO 27001:2022
ISO 27001:2022 A.12.6.1 - Management of technical vulnerabilities
ISO 27001:2022 A.14.2.1 - Secure development
ISO 27001:2022 A.12.3.1 - Configuration management
🟣 PCI DSS v4.0.1
PCI DSS 6.2 - Security patches and updates
PCI DSS 6.3.1 - Vulnerability identification
🔗 References & Sources 4
🔗
https://go.dev/cl/767860
security@golang.org
Patch
🔗
https://go.dev/issue/78803
security@golang.org
Issue Tracking
🔗
https://groups.google.com/g/golang-announce/c/qcCIEXso47M
security@golang.org
Mailing List
Third Party Advisory
🔗
https://pkg.go.dev/vuln/GO-2026-4981
security@golang.org
Vendor Advisory
📦 Affected Products / CPE 2 entries
golang:go
golang:go