Synacor Zimbra Collaboration Suite (ZCS) Cross-Site Scripting (XSS) Vulnerability. Actively exploited: CISA added this vulnerability to its Known Exploited Vulnerabilities catalog on 19/05/2025. Patch affected systems as an emergency.
| Package | Affected versions | Patched versions |
|---|---|---|
| collaboration | = 9.0.0≥ 10.0.0, < 10.0.7 | 10.0.7 |
An issue was discovered in Zimbra Collaboration (ZCS) 9.0 and 10.0. A Cross-Site Scripting (XSS) vulnerability exists in the CalendarInvite feature of the Zimbra webmail classic user interface, because of improper input validation in the handling of the calendar header. An attacker can exploit this via an email message containing a crafted calendar header with an embedded XSS payload. When a victim views this message in the Zimbra webmail classic interface, the payload is executed in the context of the victim's session, potentially leading to execution of arbitrary JavaScript code.
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