- High 7.8
- Known exploited (CISA KEV)
CVE-2026-56155
Insufficient granularity of access control in Active Directory Federation Services (AD FS) allows an authorized attacker to elevate privileges locally.
Scores
The facts
- Published
- 14 July 2026
- Last changed
- 15 July 2026
- NVD status
- Analyzed
- Severity
- High, CVSS 7.8 out of 10 (version 3.1)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- Affects
- microsoft windows 10 1607
- microsoft windows 10 1809
- microsoft windows server 2012
- microsoft windows server 2016
- microsoft windows server 2019
- Known exploited
- Yes. CISA added it to the Known Exploited Vulnerabilities catalogue on 14 July 2026.
- EPSS
- 0.3% chance of exploitation activity in the next 30 days (percentile 27).
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