CVE-2026-56155
HIGHCISA KEVEPSS 82th pctlDescription
Insufficient granularity of access control in Active Directory Federation Services (AD FS) allows an authorized attacker to elevate privileges locally.
How to fix
TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works
Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.
CVSS v3 Vector
Exploitability
Impact
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
Exploit Intelligence
Elevated risk: more likely to be exploited than 82% of all known CVEs.
Remediation due: 2026-07-28
References
Related Vulnerabilities
Other CWE-1220 vulnerabilities, ordered by exploit likelihood. View all
| CVE | Severity | CVSS | EPSS | Exploited | Fix |
|---|---|---|---|---|---|
| CVE-2025-31201 | Critical | 9.8 | 15% | KEV | Fix |
| CVE-2026-33825 | High | 7.8 | 6.7% | KEV + Ransom | Fix |
| CVE-2024-42365 | High | 7.4 | 4.7% | - | Fix |
| CVE-2026-39363 | High | 7.5 | 3.3% | - | Fix |
| CVE-2026-49170 | High | 7.8 | 2.8% | - | Fix |
| CVE-2023-43040 | Medium | 6.5 | 2.5% | - | Fix |
Common questions
How do I fix CVE-2026-56155?
Published advisories record a fix for 13 affected products. The "How to fix" section on this page lists the fixed version and source advisory for each one, so apply the entry matching what you actually run.
Is CVE-2026-56155 being actively exploited?
Yes. CVE-2026-56155 is listed in the CISA Known Exploited Vulnerabilities catalog, which means exploitation has been observed in the wild. US federal agencies were required to remediate it by 2026-07-28. Treat it as a priority whatever its CVSS score says.
How severe is CVE-2026-56155?
CVE-2026-56155 has a CVSS v3 base score of 7.8, rated important. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.
What does CVE-2026-56155 affect?
Published advisories record a fix for Windows 10 Version 1607 (Windows), Windows 10 Version 1809 (Windows), Windows Server 2012 (Windows), Windows Server 2012 (Server Core installation) (Windows), and 9 more. Only products with a sourced advisory are listed, so treat this as what we can cite rather than a complete inventory.
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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-07-15.