CVE-2026-20817
Windows Error Reporting Service Elevation of Privilege Vulnerability
- Published
- Jan 13, 2026
- Updated
- Jul 30, 2026
- Assigning CNA
- microsoft
- Evidence observed
- Aug 8, 2026
Primary CVSS
nvd · CVSS 3.1
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HLow · next 30 days
- Percentile
- 92.5%
- Model date
- Sep 21, 2026
EPSS is a statistical estimate, not a certainty or a measure of impact. Combine it with CVSS, KEV status, exposure and your environment.
Summary
Improper handling of insufficient permissions or privileges in Windows Error Reporting allows an authorized attacker to elevate privileges locally.
Sources
2Proof-of-concept exploit for CVE-2026-20817, a local privilege escalation in Windows Error Reporting (WER) via ALPC, allowing low-privileged users to execute code as SYSTEM.
Proof-of-concept exploit for CVE-2026-20817, demonstrating the vulnerability with a C-based implementation for security research and testing.
Responsible use
Use vulnerability information only on systems you own or are authorized to test. Kitploit links to public research metadata and does not store exploit code or malicious payloads.