Vulnerabilities
CVE-2026-83518: RPC Runtime Heap Overflow Enables Local Privilege Escalation on Windows
A heap-based buffer overflow in the Windows RPC Runtime (CVE‑2026‑83518) allows an attacker with local access to gain elevated privileges. The flaw is exploitable only by users who already have some level of access, making it a targeted privilege‑escalation vector. Defenders should apply the latest Microsoft patch, enforce least‑privilege policies, and monitor for anomalous local privilege changes.
What Happened
Heap-based buffer overflow in RPC Runtime allows an authorized attacker to elevate privileges locally.
A heap-based buffer overflow was discovered in the Windows RPC Runtime component. The flaw permits an attacker who already has local access to overwrite memory and execute code with higher privileges.
Affected Systems
All Windows operating systems that include the RPC Runtime service are potentially impacted, including Windows 10, Windows 11, and Windows Server 2019/2022. The vulnerability requires an authorized user context to trigger.
Impact
Once exploited, the attacker can elevate privileges locally, potentially compromising the entire system. The attack surface is limited to machines where the attacker has some level of local access.
Mitigation
- Install the latest security update from Microsoft that addresses CVE-2026-83518.
- Apply the patch to all affected Windows installations immediately.
- Enforce least-privilege for local accounts and disable unnecessary RPC services.
Monitoring Recommendations
- Track account privilege changes and anomalous local privilege escalation events.
- Use Windows Event Logs (Event ID 4670, 4672) to detect unauthorized privilege modifications.
- Deploy endpoint detection and response (EDR) solutions to flag suspicious memory writes near RPC Runtime.
Related vulnerabilities
CVE-2026-83650: Windows Media Heap Overflow Enables Local Privilege Escalation
A heap‑based buffer overflow in Windows Media components allows an authorized user to elevate privileges on the local machine. The flaw is present in all Windows 10/11 builds that ship with the Media Foundation runtime. Defenders should apply the latest MSRC update and enforce least‑privilege for media services.
Read briefing
CVE-2026-70114: Windows Kernel Heap Overflow Enables Local Privilege Escalation
Microsoft has identified a heap-based buffer overflow in the Windows kernel that allows an authorized local user to gain SYSTEM privileges. The vulnerability affects Windows 10, 11, and Windows Server 2016/2022. Defenders should apply the latest cumulative update and enforce least‑privilege controls.
Read briefing
CVE‑2026‑83678: Windows TCP/IP Heap Overflow Enables Local Privilege Escalation
A heap‑based buffer overflow in the Windows TCP/IP stack (CVE‑2026‑83678) allows a local attacker with authorized access to elevate privileges. Microsoft has issued a patch; administrators should apply it immediately and tighten local privilege controls.
Read briefing
CVE-2026-70108: Windows Win32k Heap Overflow Enables Local Privilege Escalation
Microsoft disclosed CVE‑2026‑70108, a heap‑based buffer overflow in the Win32 kernel subsystem that lets an authenticated local user elevate privileges. The flaw is present in all current Windows releases until patched. Defenders should apply the latest cumulative update and monitor for anomalous privilege changes.
Read briefing