Auth bypass in Microsoft Windows Server
CVE-2021-40456
Windows AD FS Security Feature Bypass Vulnerability
Vulnerability class: Broken Access Control
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N.
EPSS exploit prediction
EPSS: 0.023 (83.0th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 83rd percentile — 83.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.023 · newest: 0.023 · change: 0.000
Affected products
- Microsoft Windows Server — versions 20h2
- Microsoft Windows Server 2019 — versions 10.0.0
- Microsoft Windows Server 2019
- Microsoft Windows Server 2019 (Server Core Installation) — versions 10.0.0
- Microsoft Windows Server 2022 — versions 10.0.0
- Microsoft Windows Server 2022
- Microsoft Windows Server Version 2004 — versions 10.0.0
- Microsoft Windows Server Version 20h2 — versions 10.0.0
Weakness classification (CWE)
References
- portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-40456 (Patch, Vendor Advisory)
Frequently asked questions
- What is CVE-2021-40456?
- CVE-2021-40456 is a medium-severity vulnerability in Microsoft Windows Server, classified under Incorrect Authorization. CVSS score: 5.3/10. Published 2021-10-13.
- How severe is CVE-2021-40456?
- Medium severity. CVSS v3 base score is 5.3 out of 10.