{
  "id": "cve-2025-27915",
  "cveID": "CVE-2025-27915",
  "vendor": "Synacor",
  "product": "Zimbra Collaboration Suite (ZCS)",
  "vulnerabilityName": "Synacor Zimbra Collaboration Suite (ZCS) Cross-site Scripting Vulnerability",
  "shortDescription": "Synacor Zimbra Collaboration Suite (ZCS) contains a cross-site scripting vulnerability that 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 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.",
  "requiredAction": "Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.",
  "dateAdded": "2025-10-07",
  "dueDate": "2025-10-28",
  "knownRansomware": false,
  "cwes": [
    "CWE-79"
  ],
  "notes": "https://wiki.zimbra.com/wiki/Security_Center ; https://nvd.nist.gov/vuln/detail/CVE-2025-27915",
  "sources": [
    {
      "label": "NVD",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-27915"
    },
    {
      "label": "CISA KEV",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog"
    },
    {
      "label": "wiki.zimbra.com",
      "url": "https://wiki.zimbra.com/wiki/Security_Center"
    },
    {
      "label": "nvd.nist.gov",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-27915"
    }
  ],
  "cvss": {
    "score": 5.4,
    "severity": "MEDIUM",
    "version": "3.1",
    "vector": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N"
  },
  "epss": {
    "score": 0.03918,
    "percentile": 0.89697
  },
  "timeline": [
    {
      "date": "2025-10-07",
      "event": "Added to the CISA KEV catalog"
    },
    {
      "date": "2025-10-28",
      "event": "CISA remediation due date (BOD 22-01)"
    }
  ],
  "status": "past due"
}