Vulnerability details
CVE-2026-56155
Actively exploited
Microsoft Windows 10Microsoft Windows Server
Active Directory Federation Services Elevation of Privilege Vulnerability
CVSS 3.1
7.8High
Official description
Insufficient granularity of access control in Active Directory Federation Services (AD FS) allows an authorized attacker to elevate privileges locally.
CVSS scores
| Score | Version | Source | Vector |
|---|---|---|---|
| 7.8High | 3.1 | CVEProject cvelistV5 (CNA) (microsoft) | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C |
Affected products
| Vendor | Product | Versions | Source |
|---|---|---|---|
| Microsoft | Windows 10 Version 1607 | 10.0.14393.0 ≤ v < 10.0.14393.9339 | CVEProject cvelistV5 (CNA) |
| Microsoft | Windows 10 Version 1809 | 10.0.17763.0 ≤ v < 10.0.17763.9020 | CVEProject cvelistV5 (CNA) |
| Microsoft | Windows Server 2012 | 6.2.9200.0 ≤ v < 6.2.9200.26226 | CVEProject cvelistV5 (CNA) |
| Microsoft | Windows Server 2012 (Server Core installation) | 6.2.9200.0 ≤ v < 6.2.9200.26226 | CVEProject cvelistV5 (CNA) |
| Microsoft | Windows Server 2012 R2 | 6.3.9600.0 ≤ v < 6.3.9600.23291 | CVEProject cvelistV5 (CNA) |
| Microsoft | Windows Server 2012 R2 (Server Core installation) | 6.3.9600.0 ≤ v < 6.3.9600.23291 | CVEProject cvelistV5 (CNA) |
| Microsoft | Windows Server 2016 | 10.0.14393.0 ≤ v < 10.0.14393.9339 | CVEProject cvelistV5 (CNA) |
| Microsoft | Windows Server 2016 (Server Core installation) | 10.0.14393.0 ≤ v < 10.0.14393.9339 | CVEProject cvelistV5 (CNA) |
| Microsoft | Windows Server 2019 | 10.0.17763.0 ≤ v < 10.0.17763.9020 | CVEProject cvelistV5 (CNA) |
| Microsoft | Windows Server 2019 (Server Core installation) | 10.0.17763.0 ≤ v < 10.0.17763.9020 | CVEProject cvelistV5 (CNA) |
| Microsoft | Windows Server 2022 | 10.0.20348.0 ≤ v < 10.0.20348.5386 | CVEProject cvelistV5 (CNA) |
| Microsoft | Windows Server 2025 | 10.0.26100.0 ≤ v < 10.0.26100.33158 | CVEProject cvelistV5 (CNA) |
| Microsoft | Windows Server 2025 (Server Core installation) | 10.0.26100.0 ≤ v < 10.0.26100.33158 | CVEProject cvelistV5 (CNA) |
References and advisories
2- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-56155 vendor-advisorypatch
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-56155 government-resource
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Details
- Published
- 2026-07-14
- Last updated
- 2026-11-11
- State
- Published
- Assigner (CNA)
- microsoft
- Kolun priority
- 69 · High
CISA KEV catalog
- Date added
- 2026-07-14
- Due date
- 2026-07-28
- Used in ransomware
- Unknown
Exploit prediction (EPSS)
0.34%
Probability of exploitation in 30 days
28.3%
Percentile (among all CVEs)
SSVC assessment (CISA)
- Automatable
- No
- Exploitation
- Active
- Technical impact
- Total
Weaknesses (CWE)
- CWE-1220Insufficient Granularity of Access Control