{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-93631", "assignerOrgId": "9974b330-7714-4307-a722-5648477acda7", "state": "PUBLISHED", "assignerShortName": "rapid7", "dateReserved": "2026-09-18T12:22:34.911Z", "datePublished": "2026-10-23T13:23:34.952Z", "dateUpdated": "2026-10-23T13:23:34.952Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "9974b330-7714-4307-a722-5648477acda7", "shortName": "rapid7", "dateUpdated": "2026-10-23T13:23:34.952Z"}, "title": "Zimbra Collaboration Suite OAuth Extension Cross-Site Request Forgery Enables Account Linking", "datePublic": "2026-10-23T12:51:00.000Z", "problemTypes": [{"descriptions": [{"lang": "en", "cweId": "CWE-352", "description": "CWE-352 Cross-Site request forgery (CSRF)", "type": "CWE"}]}], "affected": [{"vendor": "Zimbra", "product": "Zimbra Collaboration Suite", "versions": [{"status": "affected", "version": "0", "lessThanOrEqual": "10.1.20", "versionType": "semver"}], "defaultStatus": "unaffected"}], "descriptions": [{"lang": "en", "value": "A cross-site request forgery vulnerability in the OAuth extension of Zimbra Collaboration Suite (ZCS) Network Edition allows an attacker to link an attacker-controlled external account to a victim's mailbox. The OAuth callback does not bind its state value or authorization code to the initiating Zimbra session and instead selects the destination mailbox from the browser's current authentication cookie. On a deployment with the provider configured, an attacker can induce a signed-in victim to load a callback containing a fresh code for the attacker's provider account. This creates a persistent data source that imports attacker-controlled contacts or events. With bidirectional CalDAV synchronization, appointments subsequently created or edited in the linked calendar are also disclosed to the attacker. ZCS 10.1.16 and 10.1.20 are affected.", "supportingMedia": [{"type": "text/html", "base64": false, "value": "A cross-site request forgery vulnerability in the OAuth extension of Zimbra Collaboration Suite (ZCS) Network Edition allows an attacker to link an attacker-controlled external account to a victim's mailbox. The OAuth callback does not bind its state value or authorization code to the initiating Zimbra session and instead selects the destination mailbox from the browser's current authentication cookie. On a deployment with the provider configured, an attacker can induce a signed-in victim to load a callback containing a fresh code for the attacker's provider account. This creates a persistent data source that imports attacker-controlled contacts or events. With bidirectional CalDAV synchronization, appointments subsequently created or edited in the linked calendar are also disclosed to the attacker. ZCS 10.1.16 and 10.1.20 are affected."}]}], "references": [{"url": "https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories", "tags": ["vendor-advisory"]}, {"url": "https://www.rapid7.com/blog/post/ve-breaking-zimbra-identity-boundaries-part-1/", "tags": ["related"]}], "metrics": [{"format": "CVSS", "scenarios": [{"lang": "en", "value": "GENERAL"}], "cvssV3_1": {"version": "3.1", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "LOW", "availabilityImpact": "NONE", "baseSeverity": "HIGH", "baseScore": 7.1, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/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"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Zimbra Collaboration Suite", "vendor": "Zimbra", "versions": [{"lessThanOrEqual": "10.1.20", "status": "affected", "version": "0", "versionType": "semver"}]}], "source": "cve@rapid7.com"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "A cross-site request forgery vulnerability in the OAuth extension of Zimbra Collaboration Suite (ZCS) Network Edition allows an attacker to link an attacker-controlled external account to a victim's mailbox. The OAuth callback does not bind its state value or authorization code to the initiating Zimbra session and instead selects the destination mailbox from the browser's current authentication cookie. On a deployment with the provider configured, an attacker can induce a signed-in victim to load a callback containing a fresh code for the attacker's provider account. This creates a persistent data source that imports attacker-controlled contacts or events. With bidirectional CalDAV synchronization, appointments subsequently created or edited in the linked calendar are also disclosed to the attacker. ZCS 10.1.16 and 10.1.20 are affected."}], "id": "CVE-2026-93631", "lastModified": "2026-10-23T16:44:17.950", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 7.1, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "LOW", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "REQUIRED", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N", "version": "3.1"}, "exploitabilityScore": 2.8, "impactScore": 4.2, "source": "cve@rapid7.com", "type": "Secondary"}]}, "published": "2026-10-23T14:17:57.023", "references": [{"source": "cve@rapid7.com", "url": "https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories"}, {"source": "cve@rapid7.com", "url": "https://www.rapid7.com/blog/post/ve-breaking-zimbra-identity-boundaries-part-1/"}], "sourceIdentifier": "cve@rapid7.com", "vulnStatus": "Awaiting Analysis", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-352"}], "source": "cve@rapid7.com", "type": "Secondary"}]}

{}