📄 Description (English)
Incorrect boundary conditions in the Graphics: Canvas2D component. This vulnerability affects Firefox < 149, Firefox ESR < 115.34, Firefox ESR < 140.9, Thunderbird < 149, and Thunderbird < 140.9.
🤖 AI Executive Summary
CVE-2026-4685 is a high-severity vulnerability in Mozilla Firefox and Thunderbird's Canvas2D graphics component caused by incorrect boundary condition handling (CWE-754). With a CVSS score of 7.5, this vulnerability could allow attackers to cause denial of service or potentially execute arbitrary code through specially crafted canvas operations. No public exploit is currently available, but the lack of available patches presents immediate risk to Saudi organizations relying on these browsers.
📄 Description (Arabic)
🤖 AI Intelligence Analysis Analyzed: May 1, 2026 13:00
🇸🇦 Saudi Arabia Impact Assessment
This vulnerability poses significant risk to Saudi government entities (NCA, GOSI), banking sector (SAMA-regulated institutions, major banks), healthcare organizations, and telecommunications providers (STC, Mobily) that rely on Firefox for secure communications and web access. Government employees and financial institutions using Firefox ESR versions are particularly vulnerable. The vulnerability could be exploited through malicious websites or email attachments (Thunderbird), potentially compromising confidential government and financial data. Educational institutions and research centers using Firefox are also at risk.
🏢 Affected Saudi Sectors
Government (NCA, GOSI, Ministry of Interior)
Banking and Financial Services (SAMA-regulated institutions)
Healthcare (MOH, private hospitals)
Energy (ARAMCO, SEC)
Telecommunications (STC, Mobily, Zain)
Education (Universities, research centers)
Defense and Security
🎯 MITRE ATT&CK Techniques
⚖️ Saudi Risk Score (AI)
7.8
/ 10.0
🔧 Remediation Steps (English)
IMMEDIATE ACTIONS:
1. Inventory all Firefox and Thunderbird installations across your organization, prioritizing government, banking, and healthcare systems
2. Disable Canvas2D functionality where possible through browser policies (about:config - disable canvas rendering)
3. Implement network-level controls to block access to known malicious canvas-based exploit sites
4. Deploy email gateway filtering to block suspicious attachments that may exploit this vulnerability
PATCHING GUIDANCE:
1. Monitor Mozilla security advisories for patch availability (expected Firefox 149, ESR 115.34, ESR 140.9, Thunderbird 149, 140.9)
2. Establish expedited patching procedures for Firefox/Thunderbird once patches are released
3. For ESR versions, prioritize updating to patched ESR releases immediately upon availability
4. Test patches in isolated environments before enterprise deployment
COMPENSATING CONTROLS (until patches available):
1. Restrict Firefox/Thunderbird usage to trusted networks only
2. Implement application whitelisting to prevent unauthorized browser versions
3. Deploy endpoint detection and response (EDR) solutions to monitor for Canvas2D exploitation attempts
4. Use browser isolation technology for high-risk users accessing untrusted websites
5. Implement Content Security Policy (CSP) headers on internal web applications to restrict canvas operations
DETECTION RULES:
1. Monitor for abnormal Canvas2D API calls in browser process memory
2. Alert on Firefox/Thunderbird crashes with canvas-related stack traces
3. Detect unusual memory allocation patterns during canvas rendering operations
4. Monitor for exploitation attempts via web server logs showing canvas-heavy payloads
🔧 خطوات المعالجة (العربية)
الإجراءات الفورية:
1. قم بحصر جميع تثبيتات Firefox و Thunderbird عبر مؤسستك، مع إعطاء الأولوية للأنظمة الحكومية والمصرفية والصحية
2. عطّل وظيفة Canvas2D حيث أمكن من خلال سياسات المتصفح (about:config - تعطيل عرض canvas)
3. طبّق عناصر تحكم على مستوى الشبكة لحجب الوصول إلى مواقع الاستغلال المعروفة القائمة على canvas
4. نشّر تصفية بوابة البريد الإلكتروني لحجب المرفقات المريبة التي قد تستغل هذه الثغرة
إرشادات التصحيح:
1. راقب إشعارات أمان Mozilla لتوفر التصحيحات (متوقع Firefox 149، ESR 115.34، ESR 140.9، Thunderbird 149، 140.9)
2. أنشئ إجراءات تصحيح معجلة لـ Firefox/Thunderbird بمجرد توفر التصحيحات
3. لإصدارات ESR، أعطِ الأولوية للتحديث إلى إصدارات ESR المصححة فوراً عند توفرها
4. اختبر التصحيحات في بيئات معزولة قبل النشر على مستوى المؤسسة
عناصر التحكم البديلة (حتى توفر التصحيحات):
1. قيّد استخدام Firefox/Thunderbird على الشبكات الموثوقة فقط
2. طبّق قائمة بيضاء للتطبيقات لمنع إصدارات المتصفح غير المصرح بها
3. نشّر حلول الكشف والاستجابة على نقطة النهاية (EDR) لمراقبة محاولات استغلال Canvas2D
4. استخدم تكنولوجيا عزل المتصفح للمستخدمين عالي المخاطر الذين يصلون إلى مواقع غير موثوقة
5. طبّق رؤوس سياسة أمان المحتوى (CSP) على تطبيقات الويب الداخلية لتقييد عمليات canvas
قواعد الكشف:
1. راقب استدعاءات Canvas2D API غير الطبيعية في ذاكرة عملية المتصفح
2. أصدر تنبيهات عند تعطل Firefox/Thunderbird مع تتبع مكدس متعلق بـ canvas
3. اكتشف أنماط تخصيص الذاكرة غير العادية أثناء عمليات عرض canvas
4. راقب محاولات الاستغلال عبر سجلات خادم الويب التي تظهر حمولات ثقيلة على canvas
📋 Regulatory Compliance Mapping
🟢 NCA ECC 2024
ECC 2024 A.5.1.1 - Information Security Policies and Procedures
ECC 2024 A.6.1.1 - Organization of Information Security
ECC 2024 A.8.1.1 - Asset Management
ECC 2024 A.12.2.1 - Restrictions on Software Installation
ECC 2024 A.12.6.1 - Management of Technical Vulnerabilities
🔵 SAMA CSF
SAMA CSF ID.BE-1 - Business Environment
SAMA CSF PR.IP-1 - Information Protection Processes
SAMA CSF PR.MA-2 - Address Identified Vulnerabilities
SAMA CSF DE.CM-8 - Vulnerability Scans
🟡 ISO 27001:2022
ISO 27001:2022 A.5.1 - Policies for Information Security
ISO 27001:2022 A.8.1 - Asset Management
ISO 27001:2022 A.12.6 - Management of Technical Vulnerabilities and Exposures
ISO 27001:2022 A.14.2 - Development Security
🟣 PCI DSS v4.0.1
PCI DSS 6.2 - Ensure Security Patches are Installed
PCI DSS 6.3.1 - Identify and Evaluate Vulnerabilities
PCI DSS 11.2 - Run Automated Vulnerability Scanning Tools
🔗 References & Sources 6
🔗
🔗
https://bugzilla.mozilla.org/show_bug.cgi?id=2016349
security@mozilla.org
Permissions Required
🔗
https://www.mozilla.org/security/advisories/mfsa2026-20/
security@mozilla.org
Vendor Advisory
🔗
https://www.mozilla.org/security/advisories/mfsa2026-21/
security@mozilla.org
Vendor Advisory
🔗
https://www.mozilla.org/security/advisories/mfsa2026-22/
security@mozilla.org
Vendor Advisory
🔗
https://www.mozilla.org/security/advisories/mfsa2026-23/
security@mozilla.org
https://www.mozilla.org/security/advisories/mfsa2026-24/
security@mozilla.org
📦 Affected Products / CPE 3 entries
mozilla:firefox
mozilla:firefox
mozilla:firefox