CVE-2026-56155 Details
Description
Insufficient granularity of access control in Active Directory Federation Services (AD FS) allows an authorized attacker to elevate privileges locally.
A vulnerability in Active Directory Federation Services (AD FS) allows an authorized attacker to locally elevate privileges due to insufficient granularity of access control. This issue affects multiple versions of Windows Server and Windows 10.
Users can apply the security update for this vulnerability, which is available through the Microsoft Update Catalog. Specific update details can be found in the Microsoft Knowledge Base articles KB5099444, KB5099445, KB5099535, KB5099536, KB5099540, and KB5099538.
Metrics
CVSS 4.0 Severity and Vector Strings:
No CVSS 4.0 data is available for this CVE.
CVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
CISA-ADP
Assessed Jul 15, 2026References to Advisories, Solutions, and Tools
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| URL | Source(s) | Tag(s) |
|---|---|---|
| https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-56155 | CISA-ADP | US Government Resource |
| https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-56155 | [email protected] | Vendor Advisory |
This CVE is in CISA's Known Exploited Vulnerabilities Catalog
Reference CISA's BOD 22-01 and Known Exploited Vulnerabilities Catalog for further guidance and requirements.
| Vulnerability Name | Date Added | Due Date | Required Action |
|---|---|---|---|
| Microsoft Active Directory Federation Services Insufficient Granularity of Access Control Vulnerability | Jul 14, 2026 | Jul 28, 2026 | 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. |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-1220 | Insufficient Granularity of Access Control | [email protected] |
Affected Products
| Product | Versions |
|---|---|
| microsoft windows 10 1607 | < 10.0.14393.9339 |
CPE
Remediation
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| microsoft windows 10 1809 | < 10.0.17763.9020 |
CPE
Remediation
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| microsoft windows server 2012 | r2 |
CPE
Remediation
| |
| microsoft windows server 2016 | < 10.0.14393.9339 |
CPE
Remediation
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| microsoft windows server 2019 | < 10.0.17763.9020 |
CPE
Remediation
| |
| microsoft windows server 2022 | < 10.0.20348.5386 |
CPE
Remediation
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| microsoft windows server 2025 | < 10.0.26100.33158 |
CPE
Remediation
| |
Change History
6 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Jul 15, 2026 | CVE Modified | CISA-ADP |
| Jul 15, 2026 | CVE Modified | CISA-ADP |
| Jul 14, 2026 | Initial Analysis | [email protected] |
| Jul 14, 2026 | CVE Modified | CISA-ADP |
| Jul 14, 2026 | CVE CISA KEV Update | Cybersecurity and Infrastructure Security Agency (CISA) U.S. Civilian Government |
| Jul 14, 2026 | New CVE Received | [email protected] |