CVE-2026-56155

HIGHCVSS 7.8Known Exploited

CISA Known Exploited Vulnerability

https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2026-56155 ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2026-56155; https://learn.microsoft.com/en-us/windows-server/identity/ad-fs/decommission/adfs-decommission-guide

Remediation deadline: July 28, 2026

Description

Microsoft Active Directory Federation Services contains an insufficient granularity of access control vulnerability that allows an authorized attacker to elevate privileges locally.

Timeline

Published:July 14th, 2026 5:17 PM

Last modified:July 15th, 2026 2:18 PM

Added to KEV:July 14th, 2026

CVSS Scoring

CVSS v3: 7.8 (HIGH)

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected Software

From NVD CPE configuration data

Vendors

microsoft

Products

windows_10_1607windows_10_1809windows_server_2012windows_server_2016windows_server_2019windows_server_2022windows_server_2025