CVE-2021-26855

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"http://packetstormsecurity.com/files/162736/Microsoft-Exchange-ProxyLogon-Collector.html", "tags": ["x_refsource_MISC"]}], "descriptions": [{"lang": "en-US", "value": "Microsoft Exchange Server Remote Code Execution Vulnerability"}], "problemTypes": [{"descriptions": [{"lang": "en-US", "type": "Impact", "description": "Remote Code Execution"}]}], "providerMetadata": {"orgId": "f38d906d-7342-40ea-92c1-6c4a2c6478c8", "shortName": "microsoft", "dateUpdated": "2023-12-29T20:08:56.682Z"}}}, "cveMetadata": {"cveId": "CVE-2021-26855", "state": "PUBLISHED", "dateUpdated": "2026-08-12T03:55:35.061Z", "dateReserved": "2021-02-08T00:00:00.000Z", "assignerOrgId": "f38d906d-7342-40ea-92c1-6c4a2c6478c8", "datePublished": "2021-03-02T23:55:26.000Z", "assignerShortName": "microsoft"}, "dataVersion": "5.2"}

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Este ID de CVE es diferente de CVE-2021-26412, CVE-2021-26854, CVE-2021-26857, CVE-2021-26858, CVE-2021-27065, CVE-2021-27078"}], "id": "CVE-2021-26855", "lastModified": "2026-08-19T19:22:24.100", "metrics": {"cvssMetricV2": [{"acInsufInfo": false, "baseSeverity": "HIGH", "cvssData": {"accessComplexity": "LOW", "accessVector": "NETWORK", "authentication": "NONE", "availabilityImpact": "PARTIAL", "baseScore": 7.5, "confidentialityImpact": "PARTIAL", "integrityImpact": "PARTIAL", "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P", "version": "2.0"}, "exploitabilityScore": 10.0, "impactScore": 6.4, "obtainAllPrivilege": false, "obtainOtherPrivilege": false, "obtainUserPrivilege": false, "source": "nvd@nist.gov", "type": "Primary", "userInteractionRequired": false}], "cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 9.1, "baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 5.2, "source": "secure@microsoft.com", "type": "Secondary"}, {"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 9.8, "baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 5.9, "source": "nvd@nist.gov", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2021-26855", "options": [{"exploitation": "active"}, {"automatable": "yes"}, {"technicalImpact": "total"}], "role": "CISA Coordinator", "timestamp": "2021-03-01T00:00:00+00:00", "version": "2.0.3"}}]}, "published": "2021-03-03T00:15:12.103", "references": [{"source": "secure@microsoft.com", "tags": ["Patch", "Vendor Advisory"], "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-26855"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Exploit", "Third Party Advisory", "VDB Entry"], "url": "http://packetstormsecurity.com/files/161846/Microsoft-Exchange-2019-SSRF-Arbitrary-File-Write.html"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Exploit", "Third Party Advisory", "VDB Entry"], "url": "http://packetstormsecurity.com/files/161938/Microsoft-Exchange-ProxyLogon-Remote-Code-Execution.html"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Exploit", "Third Party Advisory", "VDB Entry"], "url": "http://packetstormsecurity.com/files/162610/Microsoft-Exchange-2019-Unauthenticated-Email-Download.html"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Exploit", "Third Party Advisory", "VDB Entry"], "url": "http://packetstormsecurity.com/files/162736/Microsoft-Exchange-ProxyLogon-Collector.html"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch", "Vendor Advisory"], "url": "https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-26855"}, {"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "tags": ["US Government Resource"], "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-26855"}], "sourceIdentifier": "secure@microsoft.com", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-918"}], "source": "nvd@nist.gov", "type": "Primary"}, {"description": [{"lang": "en", "value": "CWE-918"}], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}]}

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