CVE-2026-85943
7.0HighPublished 13 Oct 2026 · NVD status: Undergoing Analysis · AI triage by gemini-3.8-flash
- Attack vector
- Local
- Complexity
- High
- Privileges needed
- Low
- User interaction
- None
- Impact
- Full C/I/A compromise
- Weakness
- CWE-122, CWE-367
Impact
A local attacker with standard user access can elevate privileges to SYSTEM or kernel execution. They need existing credentials or local code execution to trigger the race condition.
Root cause
A time-of-check to time-of-use (TOCTOU) race condition leading to a heap-based buffer overflow in the Reliable Multicast Transport Driver (RMCAST).
Affected systems
Versions not listed — check the vendor advisory.
CVSS v3.1 · CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Fix & remediation
Install the official Microsoft security update referencing CVE-2026-85943 once released; if patching must wait, disable or stop the Reliable Multicast Protocol/RMCAST driver service if not required.
AI-suggested. Run it in staging first and check it against the vendor advisory. Why?
NVD description
Time-of-check time-of-use (toctou) race condition in Reliable Multicast Transport Driver (RMCAST) allows an authorized attacker to elevate privileges locally.