{"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":"2026-09-28T12:39:55.319Z"},"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 From address. 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":[{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-09-26T03:55:49.181484Z","id":"CVE-2026-93647","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-09-28T12:39:55.319Z"}}]}}