CVE-2026-45659

{"id": "CVE-2026-45659", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-45659", "role": "CISA Coordinator", "options": [{"exploitation": "active"}, {"automatable": "no"}, {"technicalImpact": "total"}], "version": "2.0.3", "timestamp": "2026-05-26T00:00:00+00:00"}}], "cvssMetricV31": [{"type": "Secondary", "source": "secure@microsoft.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 8.8, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "HIGH"}, "impactScore": 5.9, "exploitabilityScore": 2.8}]}, "affected": [{"source": "secure@microsoft.com", "affectedData": [{"vendor": "Microsoft", "product": "Microsoft SharePoint Enterprise Server 2016", "versions": [{"status": "affected", "version": "16.0.0", "lessThan": "16.0.5552.1002", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Microsoft SharePoint Server 2019", "versions": [{"status": "affected", "version": "16.0.0", "lessThan": "16.0.10417.20128", "versionType": "custom"}], "platforms": ["x64-based Systems"]}, {"vendor": "Microsoft", "product": "Microsoft SharePoint Server Subscription Edition", "versions": [{"status": "affected", "version": "16.0.0", "lessThan": "16.0.19725.20280", "versionType": "custom"}], "platforms": ["x64-based Systems"]}]}], "published": "2026-05-22T23:16:56.273", "references": [{"url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-45659", "tags": ["Vendor Advisory"], "source": "secure@microsoft.com"}, {"url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-45659", "tags": ["US Government Resource"], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Secondary", "source": "secure@microsoft.com", "description": [{"lang": "en", "value": "CWE-502"}]}], "descriptions": [{"lang": "en", "value": "Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network."}, {"lang": "es", "value": "La deserializaci\u00f3n de datos no confiables en Microsoft Office SharePoint permite a un atacante autorizado ejecutar c\u00f3digo a trav\u00e9s de una red."}], "lastModified": "2026-07-23T11:10:00.120", "cisaActionDue": "2026-07-04", "cisaExploitAdd": "2026-07-01", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:microsoft:sharepoint_server:*:*:*:*:subscription:*:*:*", "vulnerable": true, "matchCriteriaId": "E9919927-DE08-4AE4-B9F6-2A83117EE14A", "versionEndExcluding": "16.0.19725.20280"}, {"criteria": "cpe:2.3:a:microsoft:sharepoint_server:2016:*:*:*:enterprise:*:*:*", "vulnerable": true, "matchCriteriaId": "F815EF1D-7B60-47BE-9AC2-2548F99F10E4"}, {"criteria": "cpe:2.3:a:microsoft:sharepoint_server:2019:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "6122D014-5BF1-4AF4-8B4D-80205ED7785E"}], "operator": "OR"}]}], "sourceIdentifier": "secure@microsoft.com", "cisaRequiredAction": "Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA\u2019s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA\u2019s \u201cForensics Triage Requirements\u201d (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.", "cisaVulnerabilityName": "Microsoft SharePoint Server Deserialization of Untrusted Data Vulnerability"}