CVE-2026-33371

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{"affected": [{"affectedData": [{"product": "n/a", "vendor": "n/a", "versions": [{"status": "affected", "version": "n/a"}]}], "source": "cve@mitre.org"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:synacor:zimbra_collaboration_suite:*:*:*:*:*:*:*:*", "matchCriteriaId": "E8DBE536-EAB0-48FF-A195-C0DB0A7FBCA0", "versionEndExcluding": "10.1.16", "versionStartIncluding": "10.0.0", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "An issue was discovered in Zimbra Collaboration (ZCS) 10.0 and 10.1. An XML External Entity (XXE) vulnerability exists in the Zimbra Exchange Web Services (EWS) SOAP interface due to improper handling of XML input. An authenticated attacker can submit crafted XML data that is processed by an XML parser with external entity resolution enabled. Successful exploitation may allow disclosure of sensitive local files from the server."}, {"lang": "es", "value": "Se descubri\u00f3 un problema en Zimbra Collaboration (ZCS) 10.0 y 10.1. Existe una vulnerabilidad de entidad externa XML (XXE) en la interfaz SOAP de Zimbra Exchange Web Services (EWS) debido a un manejo inadecuado de la entrada XML. Un atacante autenticado puede enviar datos XML manipulados que son procesados por un analizador XML con la resoluci\u00f3n de entidades externas habilitada. La explotaci\u00f3n exitosa puede permitir la divulgaci\u00f3n de archivos locales sensibles del servidor."}], "id": "CVE-2026-33371", "lastModified": "2026-06-17T10:37:23.410", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 4.3, "baseSeverity": "MEDIUM", "confidentialityImpact": "LOW", "integrityImpact": "NONE", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N", "version": "3.1"}, "exploitabilityScore": 2.8, "impactScore": 1.4, "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-33371", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-03-23T13:39:44.006410Z", "version": "2.0.3"}}]}, "published": "2026-03-20T14:16:16.240", "references": [{"source": "cve@mitre.org", "tags": ["Release Notes", "Vendor Advisory"], "url": "https://wiki.zimbra.com/wiki/Security_Center"}, {"source": "cve@mitre.org", "tags": ["Release Notes"], "url": "https://wiki.zimbra.com/wiki/Zimbra_Releases/10.1.16#Security_Fixes"}, {"source": "cve@mitre.org", "tags": ["Product"], "url": "https://wiki.zimbra.com/wiki/Zimbra_Responsible_Disclosure_Policy"}, {"source": "cve@mitre.org", "tags": ["Vendor Advisory"], "url": "https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories"}], "sourceIdentifier": "cve@mitre.org", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-611"}], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "[0,10.1]"}}], "enrichment": {"confidence": 100.0, "confidence_source": "manual", "scores": [{"score": 100.0, "source": "manual"}]}, "original": {"product": "n/a", "source": "cna", "vendor": "n/a"}, "product": "collaboration", "vendor": "zimbra"}], "analysis": {"en": {"generated_at": "2026-04-02T04:18:55.294731+00:00", "value": {"mitigation_remediation": ["Apply the latest Zimbra Collaboration Suite security update, at least version 10.1.16, which removes the XML entity processing flaw.", "If an update is not immediately possible, reconfigure the Zimbra XML parser to disable external entity resolution or restrict the set of allowable external entities.", "Ensure that EWS SOAP endpoints are protected behind authentication and network segmentation to limit exposure.", "Verify that no custom or legacy EWS extensions are still using unsecured XML processing before deploying a patch."], "summary": {"action": "Patch Immediately", "impact": "Exposure of local file contents via authenticated XML processing"}, "threat_synthesis": {"affected_systems": "The issue affects Zimbra Collaboration Suite releases 10.0 and 10.1. All editions of those major releases that expose the EWS SOAP interface are vulnerable. Administrators should verify whether their deployment is running any of the 10.0.x or 10.1.x branches, as the problem is specific to those major versions.", "description_and_impact": "This vulnerability allows an attacker who can authenticate to the Zimbra Exchange Web Services (EWS) SOAP interface to submit specially crafted XML that includes external entity references. The server\u2019s XML parser resolves these references, resulting in the ability to read files residing on the Zimbra server machine. The impact is the disclosure of potentially sensitive configuration files, credentials, or other internal data, compromising confidentiality. The weakness is characterized as CWE-611, a classic XML External Entity condition. No denial\u2011of\u2011service or execution path is noted, so the threat is limited to data exposure. The CVSS base score of 4.3 indicates a low\u2011to\u2011moderate severity, reflecting that the requirement for authentication and the nature of the data disclosed keep the risk profile modest compared to higher\u2011scoring bugs.", "risk_and_exploitability": "The exploit requires an authenticated user and the ability to send SOAP requests, meaning the threat vector is realistic within an internal network or for any attacker that has compromised credentials. The EPSS score of less than 1% indicates that active exploitation is currently unlikely; the vulnerability is not listed in the CISA KEV catalog. However, the low explosion probability does not negate the need for remediation, as the data exposed could be valuable. The CVSS score suggests the risk is moderate; combined with the requirement for authentication, its overall danger level is lower than Remote Code Execution bugs but still sufficient to warrant prompt action."}}}}, "created": "2026-03-20T16:30:43.743943+00:00", "updated": "2026-04-02T07:59:39.718404+00:00", "vendors": ["zimbra", "zimbra$PRODUCT$collaboration"]}