{"cve":{"cve_id":"CVE-2026-56164","is_kev":true,"kev_date_added":"2026-07-14","kev_vendor_project":"Microsoft","kev_product":"SharePoint Server","kev_vulnerability_name":"Microsoft SharePoint Server Missing Authentication for Critical Function Vulnerability","kev_short_description":"Microsoft SharePoint contains a missing authentication for critical function vulnerability that allows an unauthorized attacker to elevate privileges over a network.","kev_required_action":"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.","kev_due_date":"2026-07-17","kev_known_ransomware":false,"kev_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","kev_cwes":["CWE-306"],"epss_score":0.26636,"epss_percentile":0.97867,"epss_as_of":"2026-08-26","description":"Missing authentication for critical function in Microsoft Office SharePoint allows an unauthorized attacker to elevate privileges over a network.","published_at":"2026-07-14T17:05:12.313000Z","last_modified_at":"2026-07-14T21:10:41.693000Z","cvss_v3_score":5.3,"cvss_v3_vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N/E:F/RL:O/RC:C","cvss_v3_severity":"MEDIUM","cvss_v4_score":null,"cvss_v4_vector":null,"cvss_v4_severity":null,"ssvc_decision":null,"ssvc_exploitation":"active","ssvc_automatable":true,"ssvc_technical_impact":"partial","cwes":["CWE-306"],"nvd_references":["https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-56164"],"vuln_status":"Analyzed","trending_score":null,"is_trending":false,"has_trended":false,"trended_number_one":false,"trending_peak_score":null,"trending_peak_rank":null,"started_trending_at":null,"trended_number_one_at":null,"summary_generated":null,"summary_generated_at":null,"summary_model":null,"created_at":"2026-07-14T18:33:20.779180Z","updated_at":"2026-07-15T17:28:29.371862Z"},"effective_severity":"MEDIUM","badges":["kev"],"impact_analysis":[],"cvss_v3_decoded":{"version":"3.1","metrics":[{"metric":"AV","name":"Attack 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2016","version_start":"16.0.0","version_start_inclusive":true,"version_end":"16.0.5561.1001","version_end_inclusive":false,"cpe23_uri":"cve5:microsoft:microsoft-sharepoint-enterprise-server-2016:16.0.0:16.0.5561.1001"},{"vendor_slug":"microsoft","vendor_name":"microsoft","product_slug":"microsoft-sharepoint-server-2019","product_name":"Microsoft SharePoint Server 2019","version_start":"16.0.0","version_start_inclusive":true,"version_end":"16.0.10417.20175","version_end_inclusive":false,"cpe23_uri":"cve5:microsoft:microsoft-sharepoint-server-2019:16.0.0:16.0.10417.20175"},{"vendor_slug":"microsoft","vendor_name":"microsoft","product_slug":"microsoft-sharepoint-server-subscription-edition","product_name":"Microsoft SharePoint Server Subscription Edition","version_start":"16.0.0","version_start_inclusive":true,"version_end":"16.0.19725.20434","version_end_inclusive":false,"cpe23_uri":"cve5:microsoft:microsoft-sharepoint-server-subscription-edition:16.0.0:16.0.19725.20434"},{"vendor_slug":"microsoft","vendor_name":"microsoft","product_slug":"sharepoint-server","product_name":"sharepoint_server","version_start":null,"version_start_inclusive":null,"version_end":"16.0.19725.20434","version_end_inclusive":false,"cpe23_uri":"cpe:2.3:a:microsoft:sharepoint_server:*:*:*:*:subscription:*:*:*"},{"vendor_slug":"microsoft","vendor_name":"microsoft","product_slug":"sharepoint-server","product_name":"sharepoint_server","version_start":"2016","version_start_inclusive":true,"version_end":"2016","version_end_inclusive":true,"cpe23_uri":"cpe:2.3:a:microsoft:sharepoint_server:2016:*:*:*:enterprise:*:*:*"},{"vendor_slug":"microsoft","vendor_name":"microsoft","product_slug":"sharepoint-server","product_name":"sharepoint_server","version_start":"2019","version_start_inclusive":true,"version_end":"2019","version_end_inclusive":true,"cpe23_uri":"cpe:2.3:a:microsoft:sharepoint_server:2019:*:*:*:*:*:*:*"}],"exploit_refs":[],"news":[],"references":[{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-56164","source_type":"VENDOR_ADVISORY","tags":["advisory"]}],"timeline":[{"type":"cisa_reported","at":"2026-07-14T00:00:00Z","label":"Added to CISA KEV catalog","source":"kev"},{"type":"published","at":"2026-07-14T17:05:12.313000Z","label":"CVE published","source":null},{"type":"ssvc_changed","at":"2026-07-14T20:34:20.783664Z","label":"SSVC decision revised","source":"vulnrichment"},{"type":"ssvc_changed","at":"2026-07-14T20:34:20.783664Z","label":"SSVC decision revised","source":"vulnrichment"},{"type":"ssvc_changed","at":"2026-07-14T20:34:20.783664Z","label":"SSVC decision revised","source":"vulnrichment"}]}