Zimbra Zero-Day Exploited to Target Brazilian Military via Malicious ICS Files

A now patched security vulnerability in Zimbra Collaboration was exploited as a zero-day earlier this year in cyber attacks targeting the Brazilian military.
Tracked as CVE-2025-27915 (CVSS score: 5.4), the vulnerability is a stored cross-site scripting (XSS) vulnerability in the Classic Web Client that arises as a result of insufficient sanitization of HTML content in ICS calendar files,