Microsoft November 2026 Patch Tuesday fixes 1093 CVEs, one exploited
Outlook spoofing CVE-2026-124194, used as a zero-day, leaks NTLMv2 hashes when a crafted Office file is opened.
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CVE-2026-83563
Local privilege escalation via heap overflow in Winlogon
- CVSS 3.1
- 7.8 high
- EPSS
- —
- Published
- ·
- Modified
AI analysisSummaries by Vani AI
A heap-based buffer overflow in Winlogon lets an attacker who already has a local authorized account elevate privileges. No user interaction is required. Successful exploitation yields high impact on confidentiality, integrity, and availability. Microsoft has not listed affected builds or a fixed version.
What to do: Apply Microsoft's update for CVE-2026-83563. No workaround is stated.
| Product | Affected |
|---|---|
| Microsoft Winlogon | — |
Estimated exposure
No basis for an estimate.
Order-of-magnitude estimate by the model from install counts, market share and public scan data it knows; verify before quoting.
Description · NVD
Heap-based buffer overflow in Winlogon allows an authorized attacker to elevate privileges locally.
- Weakness
- CWE-122
- Vector
- CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H