{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-93647", "assignerOrgId": "9974b330-7714-4307-a722-5648477acda7", "state": "PUBLISHED", "assignerShortName": "rapid7", "dateReserved": "2026-09-18T12:22:43.194Z", "datePublished": "2026-09-25T13:58:05.368Z", "dateUpdated": "2026-09-26T03:55:48.781Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "9974b330-7714-4307-a722-5648477acda7", "shortName": "rapid7", "dateUpdated": "2026-09-25T13:58:05.368Z"}, "title": "Zimbra Collaboration Suite Classic Web Client Stored Cross-Site Scripting via Crafted Calendar COUNTER Message From Address", "datePublic": "2026-09-25T13:53:00.000Z", "problemTypes": [{"descriptions": [{"lang": "en", "cweId": "CWE-79", "description": "CWE-79 Improper neutralization of input during web page generation ('cross-site scripting')", "type": "CWE"}]}], "affected": [{"vendor": "Zimbra", "product": "Zimbra Collaboration Suite (ZCS)", "versions": [{"status": "affected", "version": "0", "lessThan": "10.1.21", "versionType": "semver"}], "defaultStatus": "unaffected"}], "descriptions": [{"lang": "en", "value": "An unauthenticated calendar sender can place active markup in a COUNTER message's RFC\u00a0From\u00a0address. Selecting the message in Zimbra Classic triggers stored XSS, allowing the attacker to access mailbox data and act as the victim.", "supportingMedia": [{"type": "text/html", "base64": false, "value": "An unauthenticated calendar sender can place active markup in a COUNTER message's RFC&nbsp;<code>From</code>&nbsp;address. Selecting the message in Zimbra Classic triggers stored XSS, allowing the attacker to access mailbox data and act as the victim."}]}], "references": [{"url": "https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories", "tags": ["vendor-advisory"]}], "metrics": [{"format": "CVSS", "scenarios": [{"lang": "en", "value": "GENERAL"}], "cvssV3_1": {"version": "3.1", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "CHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "NONE", "baseSeverity": "CRITICAL", "baseScore": 9.3, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N"}}], "credits": [{"lang": "en", "value": "Jonah Burgess (CryptoCat), Senior Security Researcher, Rapid7", "type": "finder"}], "source": {"discovery": "UNKNOWN"}, "x_generator": {"engine": "Vulnogram 1.0.5"}}, "adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"timestamp": "2026-09-25T00:00:00+00:00", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "total"}], "role": "CISA Coordinator", "version": "2.0.3", "id": "CVE-2026-93647"}}}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-09-26T03:55:48.781Z"}}]}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Zimbra Collaboration Suite (ZCS)", "vendor": "Zimbra", "versions": [{"lessThan": "10.1.21", "status": "affected", "version": "0", "versionType": "semver"}]}], "source": "[email protected]"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "An unauthenticated calendar sender can place active markup in a COUNTER message's RFC\u00a0From\u00a0address. Selecting the message in Zimbra Classic triggers stored XSS, allowing the attacker to access mailbox data and act as the victim."}], "id": "CVE-2026-93647", "lastModified": "2026-09-26T04:17:52.143", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 9.3, "baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "CHANGED", "userInteraction": "REQUIRED", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N", "version": "3.1"}, "exploitabilityScore": 2.8, "impactScore": 5.8, "source": "[email protected]", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-93647", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "total"}], "role": "CISA Coordinator", "timestamp": "2026-09-25T00:00:00+00:00", "version": "2.0.3"}}]}, "published": "2026-09-25T14:17:23.673", "references": [{"source": "[email protected]", "url": "https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories"}], "sourceIdentifier": "[email protected]", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-79"}], "source": "[email protected]", "type": "Secondary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,10.1.21)"}}], "enrichment": {"confidence": 93.0, "confidence_source": "matching", "scores": [{"score": 93.0, "source": "matching"}]}, "original": {"product": "Zimbra Collaboration Suite (ZCS)", "source": "cna", "vendor": "Zimbra"}, "product": "zimbra_collaboration_suite", "vendor": "zimbra"}], "created": "2026-09-25T18:00:20.828583+00:00", "updated": "2026-09-26T22:30:56.273231+00:00", "vendors": ["zimbra", "zimbra$PRODUCT$zimbra_collaboration_suite"]}