📄 Description (English)
An out-of-bounds read flaw was found in the X.Org X server and Xwayland in __glXDisp_ChangeDrawableAttributes(). A wrong size validation check can read a client-controlled number of bytes, exceeding the request buffer, leading to information disclosure. A write path also exists but requires byte-swapped clients which is disabled by default.
🤖 AI Executive Summary
CVE-2026-50262 is a medium-severity out-of-bounds read vulnerability in X.Org X server and Xwayland that allows information disclosure through improper buffer size validation in the __glXDisp_ChangeDrawableAttributes() function. While no public exploit is available and patches are not yet released, the vulnerability could expose sensitive memory contents to local or remote attackers depending on X server exposure. Organizations should monitor for vendor patches and implement compensating controls to restrict X server access.
📄 Description (Arabic)
🤖 AI Intelligence Analysis Analyzed: Jun 5, 2026 16:18
🇸🇦 Saudi Arabia Impact Assessment
This vulnerability primarily affects Saudi government entities, research institutions, and technology companies running X.Org-based desktop environments or Xwayland on Linux systems. High-risk sectors include: (1) Government/NCA — systems using X11 for administrative workstations; (2) ARAMCO and energy sector — engineering workstations running CAD/visualization software dependent on X server; (3) Universities and research centers — systems with X-based scientific computing; (4) Telecom/STC — infrastructure management systems. The impact is moderate as X server exposure is typically limited to local networks or specific use cases, but information disclosure could compromise credentials or sensitive technical data.
🏢 Affected Saudi Sectors
Government/NCA
Energy/ARAMCO
Education/Universities
Telecom/STC
Technology/IT Services
Research Institutions
🎯 MITRE ATT&CK Techniques
T1005 — Data from Local System (out-of-bounds read to access local memory)
T1040 — Traffic Capture or Redirection (X protocol interception if network X11 enabled)
T1020 — Automated Exfiltration (information disclosure through memory read)
T1057 — Process Discovery (reconnaissance of X server processes)
⚖️ Saudi Risk Score (AI)
5.2
/ 10.0
🔧 Remediation Steps (English)
Immediate Actions:
1. Inventory all systems running X.Org X server or Xwayland (check 'X -version' or 'Xwayland --version')
2. Restrict X server access to trusted local users only; disable network X11 forwarding (set 'X11Forwarding no' in sshd_config)
3. Implement principle of least privilege for X server socket permissions (verify /tmp/.X11-unix permissions are 1777)
4. Monitor vendor security advisories (freedesktop.org, distribution maintainers) for patch availability
Compensating Controls (until patch available):
5. Run X server with reduced privileges using user namespaces if supported
6. Disable GLX extension if not required: add 'Option "Disable" "GLX"' in xorg.conf
7. Use Wayland as alternative display server where possible (if not affected by same vulnerability)
8. Implement network segmentation to isolate systems running X server from untrusted networks
Detection Rules:
9. Monitor for unusual X protocol requests to __glXDisp_ChangeDrawableAttributes() using strace or X11 protocol analyzers
10. Alert on attempts to read beyond allocated buffer sizes in X server logs
11. Track memory access patterns for X server processes using auditd rules targeting GLX operations
🔧 خطوات المعالجة (العربية)
الإجراءات الفورية:
1. حصر جميع الأنظمة التي تقوم بتشغيل خادم X.Org أو Xwayland (تحقق من 'X -version' أو 'Xwayland --version')
2. تقييد الوصول إلى خادم X للمستخدمين المحليين الموثوقين فقط؛ تعطيل إعادة توجيه X11 عبر الشبكة (اضبط 'X11Forwarding no' في sshd_config)
3. تطبيق مبدأ الامتياز الأقل لأذونات مقبس خادم X (تحقق من أذونات /tmp/.X11-unix وهي 1777)
4. مراقبة تنبيهات الأمان من البائعين (freedesktop.org، مسؤولو التوزيع) لتوفر التصحيحات
الضوابط التعويضية (حتى توفر التصحيح):
5. تشغيل خادم X بامتيازات منخفضة باستخدام مساحات الأسماء للمستخدمين إن أمكن
6. تعطيل امتداد GLX إذا لم يكن مطلوباً: أضف 'Option "Disable" "GLX"' في xorg.conf
7. استخدام Wayland كخادم عرض بديل حيث أمكن (إذا لم تتأثر بنفس الثغرة)
8. تطبيق تقسيم الشبكة لعزل الأنظمة التي تقوم بتشغيل خادم X عن الشبكات غير الموثوقة
قواعد الكشف:
9. مراقبة طلبات بروتوكول X غير العادية إلى __glXDisp_ChangeDrawableAttributes() باستخدام strace أو محللات بروتوكول X11
10. تنبيه عند محاولات القراءة بعد حدود المخزن المؤقت المخصص في سجلات خادم X
11. تتبع أنماط الوصول إلى الذاكرة لعمليات خادم X باستخدام قواعد auditd التي تستهدف عمليات GLX
📋 Regulatory Compliance Mapping
🟢 NCA ECC 2024
A.5.1.1 — Information security policies and procedures (X server access control)
A.6.1.1 — Internal organization (segregation of X server systems)
A.8.1.1 — User endpoint devices (workstation security for X-based systems)
A.8.2.1 — Privileged access rights (principle of least privilege for X server)
A.8.3.1 — Information access restriction (limiting X server network exposure)
🔵 SAMA CSF
ID.AM-2 — Asset Management (inventory X.Org/Xwayland systems)
PR.AC-1 — Access Control (restrict X server access to authorized users)
PR.AC-4 — Access Control (implement least privilege for X server processes)
DE.CM-1 — Detection and Analysis (monitor X protocol anomalies)
RS.MI-2 — Response and Recovery (mitigate information disclosure impact)
🟡 ISO 27001:2022
A.5.1.1 — Information security policies (X server security policy)
A.6.1.2 — Information security roles and responsibilities
A.8.1.1 — User endpoint devices (secure X server configuration)
A.8.2.1 — Privileged access rights (least privilege principle)
A.8.3.1 — Access to information and other assets (network segmentation)
A.12.6.1 — Management of technical vulnerabilities (patch management)
🔗 References & Sources 5
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https://access.redhat.com/security/cve/CVE-2026-50262
secalert@redhat.com
https://bugzilla.redhat.com/show_bug.cgi?id=2485387
secalert@redhat.com
https://gitlab.freedesktop.org/xorg/xserver/-/commit/6d459e4daf715bea8abdafa8fb130be2f8...
secalert@redhat.com
https://lists.x.org/archives/xorg-announce/2026-June/003702.html
secalert@redhat.com
https://redhat.atlassian.net/browse/PSIRTSUPT-16950
secalert@redhat.com