{"identifier":"CVE-2026-56164","cve":{"id":"CVE-2026-56164","description":"Missing authentication for critical function in Microsoft Office SharePoint allows an unauthorized attacker to elevate privileges over a network.","published":"2026-07-14T17:17:09.907000+00:00","modified":"2026-07-14T21:10:41.693000+00:00","status":"Analyzed","score":5.3,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","cvss_version":"3.1","affected":[{"criteria":"cpe:2.3:a:microsoft:sharepoint_server:*:*:*:*:subscription:*:*:*","versionStartIncluding":"","versionStartExcluding":"","versionEndIncluding":"","versionEndExcluding":"16.0.19725.20434"},{"criteria":"cpe:2.3:a:microsoft:sharepoint_server:2016:*:*:*:enterprise:*:*:*","versionStartIncluding":"","versionStartExcluding":"","versionEndIncluding":"","versionEndExcluding":""},{"criteria":"cpe:2.3:a:microsoft:sharepoint_server:2019:*:*:*:*:*:*:*","versionStartIncluding":"","versionStartExcluding":"","versionEndIncluding":"","versionEndExcluding":""}],"weaknesses":["CWE-306"],"references":[{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-56164","source":"secure@microsoft.com","tags":["Vendor Advisory"]},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-56164","source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","tags":["US Government Resource"]}],"kev":{"cveID":"CVE-2026-56164","vendorProject":"Microsoft","product":"SharePoint Server","vulnerabilityName":"Microsoft SharePoint Server Missing Authentication for Critical Function Vulnerability","dateAdded":"2026-07-14","shortDescription":"Microsoft SharePoint contains a missing authentication for critical function vulnerability that allows an unauthorized attacker to elevate privileges over a network.","requiredAction":"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.","dueDate":"2026-07-17","knownRansomwareCampaignUse":"Unknown","forensicTriage":"Yes","notes":"https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2026-56164 ; 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-2026-56164","cwes":["CWE-306"]},"kev_checked":true,"metrics":{"cvssMetricV31":[{"source":"secure@microsoft.com","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","baseScore":5.3,"baseSeverity":"MEDIUM","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"LOW","availabilityImpact":"NONE"},"exploitabilityScore":3.9,"impactScore":1.4},{"source":"nvd@nist.gov","type":"Primary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","baseScore":9.8,"baseSeverity":"CRITICAL","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"},"exploitabilityScore":3.9,"impactScore":5.9}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2026-07-14T18:45:11.388695Z","id":"CVE-2026-56164","options":[{"exploitation":"active"},{"automatable":"yes"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"configurations":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:a:microsoft:sharepoint_server:*:*:*:*:subscription:*:*:*","versionEndExcluding":"16.0.19725.20434","matchCriteriaId":"5FA63EA8-B225-4E35-A6A3-DBDECF5AC4C8"},{"vulnerable":true,"criteria":"cpe:2.3:a:microsoft:sharepoint_server:2016:*:*:*:enterprise:*:*:*","matchCriteriaId":"F815EF1D-7B60-47BE-9AC2-2548F99F10E4"},{"vulnerable":true,"criteria":"cpe:2.3:a:microsoft:sharepoint_server:2019:*:*:*:*:*:*:*","matchCriteriaId":"6122D014-5BF1-4AF4-8B4D-80205ED7785E"}]}]}],"source":"nvd","retrieved_at":"2026-10-29T15:19:27.121665+00:00","exploited":true,"kev_stale":false,"products":["microsoft / sharepoint server"],"priority":{"label":"Known exploitation: prioritize review","reasons":["CISA KEV lists real-world exploitation."]},"epss":{"probability":0.01011,"percentile":0.63056,"date":"2026-10-28","stale":false},"version_assessment":null},"news":[],"campaigns":[],"domains":[{"domain":"msrc.microsoft.com","source_url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-56164","investigate_url":"https://investigate.aeglixmind.com/#msrc.microsoft.com"},{"domain":"www.cisa.gov","source_url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-56164","investigate_url":"https://investigate.aeglixmind.com/#www.cisa.gov"}],"arsenal_url":"https://arsenal.aeglixmind.com/?cve=CVE-2026-56164","catalog_url":"https://cves.aeglixmind.com/cve/CVE-2026-56164","research_url":"https://investigate.aeglixmind.com/research/cve/CVE-2026-56164","coverage":{"news_candidates_checked":0,"campaign_candidates_checked":0,"bounded":false,"notice":"Exact CVE mentions in stored public excerpts and reviewed campaign content only. 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