KEV · Actively exploited
CVE-2026-56155
HIGH 7.8
KEV
Insufficient granularity of access control in Active Directory Federation Services (AD FS) allows an authorized attacker to elevate privileges locally.
Attack vector : Local
No user interaction
Show raw CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS
2.33%
above median
percentile 82.0%
CISA Known Exploited Vulnerability
- Added to KEV
- 2026-07-14
- Remediation deadline
- 2026-07-28
- Required action
- Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
- Ransomware
- Unknown (not documented by CISA)
OS versions that fix this CVE
This CVE is resolved by the following OS security releases. Update the OS to at least the listed version.
- Windows Server 2025 Fixed in 10.0.26100.33158
- Windows Server 2022 Fixed in 10.0.20348.5386
- Windows Server 2019 Fixed in 10.0.17763.9020
- Windows Server 2016 Fixed in 10.0.14393.9339
- Windows 10 1809 · 2018-09 Fixed in 10.0.17763.9020
- Windows 10 1607 · 2016-07 Fixed in 10.0.14393.9339