{"id":"CVE-2025-27915","url":"https://www.cyber-defence.io/tools/cve/CVE-2025-27915","generatedAt":"2026-10-31T08:11:48.507Z","title":"Synacor Zimbra Collaboration Suite (ZCS) Cross-site Scripting Vulnerability","description":"An issue was discovered in Zimbra Collaboration (ZCS) 9.0 and 10.0 and 10.1. A stored cross-site scripting (XSS) vulnerability exists in the Classic Web Client due to insufficient sanitization of HTML content in ICS files. When a user views an e-mail message containing a malicious ICS entry, its embedded JavaScript executes via an ontoggle event inside a <details> tag. This allows an attacker to run arbitrary JavaScript within the victim's session, potentially leading to unauthorized actions such as setting e-mail filters to redirect messages to an attacker-controlled address. As a result, an attacker can perform unauthorized actions on the victim's account, including e-mail redirection and data exfiltration.","published":"2025-03-12T15:15:40.000Z","lastModified":"2026-06-17T09:04:23.000Z","status":"Analyzed","sourceIdentifier":"cve@mitre.org","cvss":{"version":"3.1","score":5.4,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N"},"cwe":["CWE-79"],"affected":["synacor/zimbra collaboration suite"],"epss":{"score":0.04064,"percentile":0.90652,"date":"2026-10-30","history":[]},"kev":{"listed":true,"dateAdded":"2025-10-07","dueDate":"2025-10-28","knownRansomwareCampaignUse":"Unknown","notes":"Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.\nhttps://wiki.zimbra.com/wiki/Security_Center ; https://nvd.nist.gov/vuln/detail/CVE-2025-27915"},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"urgent","text":"Known to be exploited in the wild (CISA KEV, CISA remediation deadline 28 October 2025). Treat as an emergency change: patch or isolate now, then hunt for prior compromise."},"changes":[],"references":[{"url":"https://wiki.zimbra.com/wiki/Security_Center","tags":["Release Notes"],"source":"cve@mitre.org"},{"url":"https://wiki.zimbra.com/wiki/Zimbra_Releases/10.0.13#Security_Fixes","tags":["Release Notes"],"source":"cve@mitre.org"},{"url":"https://wiki.zimbra.com/wiki/Zimbra_Releases/10.1.5#Security_Fixes","tags":["Release Notes"],"source":"cve@mitre.org"},{"url":"https://wiki.zimbra.com/wiki/Zimbra_Releases/9.0.0/P44#Security_Fixes","tags":["Release Notes"],"source":"cve@mitre.org"},{"url":"https://strikeready.com/blog/0day-ics-attack-in-the-wild/","tags":["Exploit","Third Party Advisory"],"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-27915","tags":["US Government Resource"],"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2025-27915","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}