{"id":"CVE-2023-37580","published":"2023-07-31T16:15:10Z","modified":"2026-06-17T06:08:30Z","title":"Synacor Zimbra Collaboration Suite (ZCS) Cross-Site Scripting (XSS) Vulnerability","vendor":"Synacor","product":"Zimbra Collaboration Suite (ZCS)","tier":"core","eol":null,"description":{"text":"Zimbra Collaboration (ZCS) 8 before 8.8.15 Patch 41 allows XSS in the Zimbra Classic Web Client.","provenance":"source","from":"NVD"},"summary":{"text":"The flaw is a cross-site scripting (XSS) vulnerability in the Zimbra Classic Web Client, a component of Synacor's Zimbra Collaboration Suite (ZCS) affecting versions 8 before 8.8.15 Patch 41. An attacker can inject script into the web client to run in a victim's browser, which requires network access and no authentication but does require the victim to interact with the crafted content.","provenance":"ai","model":"claude-haiku-5-5","generatedAt":"2026-10-31T05:10:40Z"},"cvss":{"score":6.1,"severity":"MEDIUM","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","provenance":"source","from":"NVD"},"epss":{"score":0.49083,"percentile":0.98882,"date":"2026-10-30","provenance":"source"},"kev":{"dateAdded":"2023-07-27","dueDate":"2023-08-17","ransomware":false,"requiredAction":"Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.","notes":"https://wiki.zimbra.com/wiki/Security_Center ;  https://nvd.nist.gov/vuln/detail/CVE-2023-37580","provenance":"source"},"vulncheckKev":{"dateAdded":"2023-06-29","exploitedFirstSeen":"2023-06-29","ransomware":false,"evidence":[{"url":"https://docs.google.com/spreadsheets/d/1lkNJ0uQwbeC1ZTRrxdtuPLCIl7mlUreoKfSIgajnSyY/edit","date":"2023-06-29"},{"url":"https://twitter.com/maddiestone/status/1679542322772721664","date":"2023-07-13"},{"url":"https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json","date":"2023-07-27"},{"url":"https://blog.google/threat-analysis-group/zimbra-0-day-used-to-target-international-government-organizations/","date":"2023-11-16"},{"url":"https://ti.qianxin.com/uploads/2024/02/02/dcc93e586f9028c68e7ab34c3326ff31.pdf","date":"2024-02-02"},{"url":"https://www.trustwave.com/hubfs/Web/Library/Documents_pdf/2024_Trustwave_Public_Sector_Threat_Landscape.pdf","date":"2024-05-14"},{"url":"https://www.rapid7.com/globalassets/_pdfs/research/rapid7_2024_attack_intelligence_report.pdf","date":"2024-05-21"}],"evidenceTotal":7,"provenance":"source"},"exploited":true,"otx":{"pulseCount":50,"pulses":[{"name":"Actively_Exploited_Kev | Oct 29, 2026","url":"https://otx.alienvault.com/pulse/6ae20c1db17e7057ae7d9ad1","created":"2026-10-28"},{"name":"Actively_Exploited_Kev | Oct 28, 2026","url":"https://otx.alienvault.com/pulse/6ae0ba7e0e2a97ff7b218819","created":"2026-10-27"},{"name":"Actively_Exploited_Kev | Oct 27, 2026","url":"https://otx.alienvault.com/pulse/6adf68b85c3e852f3c111d18","created":"2026-10-26"},{"name":"Actively_Exploited_Kev | Oct 24, 2026","url":"https://otx.alienvault.com/pulse/6adb740e397c3ad4799aa4cd","created":"2026-10-23"},{"name":"Actively_Exploited_Kev | Oct 23, 2026","url":"https://otx.alienvault.com/pulse/6ada236fcfba2dfa730ea482","created":"2026-10-22"},{"name":"Actively_Exploited_Kev | Oct 22, 2026","url":"https://otx.alienvault.com/pulse/6ad8d33a077cbb5cab524d80","created":"2026-10-21"},{"name":"Actively_Exploited_Kev | Oct 21, 2026","url":"https://otx.alienvault.com/pulse/6ad78130c4d1ac2be83a8b6d","created":"2026-10-20"},{"name":"Actively_Exploited_Kev | Oct 20, 2026","url":"https://otx.alienvault.com/pulse/6ad62f63c24a405a3423cc13","created":"2026-10-19"},{"name":"Actively_Exploited_Kev | Oct 19, 2026","url":"https://otx.alienvault.com/pulse/6ad4dda174e5797d0bd238b7","created":"2026-10-18"},{"name":"Actively_Exploited_Kev | Oct 18, 2026","url":"https://otx.alienvault.com/pulse/6ad38c22e1848f8189d1c121","created":"2026-10-17"}],"provenance":"machine"},"cwes":[{"id":"CWE-79","name":"Improper Neutralization of Input During Web Page Generation"}],"references":[{"url":"http://www.openwall.com/lists/oss-security/2023/11/17/2","tags":["Mailing List","Patch"]},{"url":"https://wiki.zimbra.com/wiki/Security_Center","tags":["Release Notes"]},{"url":"https://wiki.zimbra.com/wiki/Zimbra_Responsible_Disclosure_Policy","tags":["Not Applicable"]},{"url":"http://www.openwall.com/lists/oss-security/2023/11/17/2","tags":["Mailing List","Patch"]},{"url":"https://wiki.zimbra.com/wiki/Security_Center","tags":["Release Notes"]},{"url":"https://wiki.zimbra.com/wiki/Zimbra_Responsible_Disclosure_Policy","tags":["Not Applicable"]},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-37580","tags":["US Government Resource"]}],"techniques":[{"id":"T1204.001","name":"Malicious Link","tactics":["execution"],"provenance":"ai","basis":"ai-mapping","bases":["ai-mapping"],"basisDetail":"claude-haiku-5-5: user clicks malicious link triggering XSS","mappingType":"exploitation_technique","evidence":[{"from":"description","quote":"allows XSS in the Zimbra Classic Web Client","start":52,"end":95}],"model":"claude-haiku-5-5","confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, not expert-reviewed)"},{"id":"T1059.007","name":"JavaScript","tactics":["execution"],"provenance":"ai","basis":"ai-mapping","bases":["ai-mapping"],"basisDetail":"claude-haiku-5-5: XSS executes attacker JavaScript in browser","mappingType":"primary_impact","evidence":[{"from":"description","quote":"allows XSS in the Zimbra Classic Web Client","start":52,"end":95}],"model":"claude-haiku-5-5","confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, not expert-reviewed)"}],"reports":[],"affected":[],"advisories":[],"euvd":{"id":"EUVD-2023-41465","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2023-41465","exploited":true,"exploitedSince":"2023-07-27","provenance":"source"},"exploits":[],"exploitSources":{"nuclei":[{"id":"CVE-2023-37580","name":"Zimbra Collaboration Suite (ZCS) v.8.8.15 - Cross-Site 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(NVD)","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-37580","provenance":"source"}],"speed":{"daysToPublicExploit":null,"firstExploitFrom":null,"daysToKev":null},"priority":{"score":67.0,"factors":[{"name":"In a KEV catalog","points":35.0,"detail":"listed in CISA KEV and VulnCheck KEV"},{"name":"Recent KEV listing","points":0.0,"detail":"added 1220 days ago"},{"name":"Known ransomware use","points":0.0,"detail":"not known"},{"name":"EPSS percentile","points":19.78,"detail":"percentile 0.9888"},{"name":"Named in threat reports","points":0.0,"detail":"0 reports"},{"name":"Public exploit code","points":5.0,"detail":"1 nuclei template"},{"name":"Mentioned in OTX pulses","points":3.0,"detail":"50 pulses"},{"name":"CVSS severity","points":4.27,"detail":"base score 6.1"},{"name":"End-of-life product","points":0.0,"detail":"supported or unknown"}]},"lineage":{"familyId":"fam-class-synacor-zimbra-collaboration-suite-zcs-cwe-79"}}