VULNERABILITY INTELLIGENCE

CVE-2025-27915

CVSS score5.4 MEDIUM
EPSS probability4.06%
CISA KEVKnown exploited vulnerability
Published2025-03-12
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

Known Exploited Vulnerability

Synacor Zimbra Collaboration Suite (ZCS) Cross-site Scripting Vulnerability

Vendor / product: Synacor / Zimbra Collaboration Suite (ZCS)

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.

Weakness classification

  • 134c704f-9b21-4f2e-91b3-4a467353bcc0: CWE-79

Primary references