{"id":"CVE-2026-56155","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-56155","generatedAt":"2026-10-28T13:14:36.673Z","title":"Microsoft Active Directory Federation Services Insufficient Granularity of Access Control Vulnerability ","description":"Insufficient granularity of access control in Active Directory Federation Services (AD FS) allows an authorized attacker to elevate privileges locally.","published":"2026-07-14T17:17:10.000Z","lastModified":"2026-07-15T14:18:24.000Z","status":"Analyzed","sourceIdentifier":"secure@microsoft.com","cvss":{"version":"3.1","score":7.8,"severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"},"cwe":["CWE-1220"],"affected":["microsoft/windows 10 1607","microsoft/windows 10 1809","microsoft/windows server 2012","microsoft/windows server 2016","microsoft/windows server 2019","microsoft/windows server 2022","microsoft/windows server 2025"],"epss":{"score":0.00346,"percentile":0.28028,"date":"2026-10-27","history":[]},"kev":{"listed":true,"dateAdded":"2026-07-14","dueDate":"2026-07-28","knownRansomwareCampaignUse":"Unknown","notes":"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.\nhttps://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"},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"urgent","text":"Known to be exploited in the wild (CISA KEV, CISA remediation deadline 28 July 2026). Treat as an emergency change: patch or isolate now, then hunt for prior compromise."},"changes":[],"references":[{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-56155","tags":["Vendor Advisory"],"source":"secure@microsoft.com"},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-56155","tags":["US Government Resource"],"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-56155","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}