CISA Known Exploited Vulnerability

This vulnerability is actively exploited in the wild and listed in the CISA Known Exploited Vulnerabilities catalog.

Remediation Deadline: Jun 9, 2025

CVE-2024-27443

High

EPSS 32.4%CISA KEV

Synacor/Zimbra Collaboration Suite (ZCS)

Description

Zimbra Collaboration contains a cross-site scripting (XSS) vulnerability in the CalendarInvite feature of the Zimbra webmail classic user interface. An attacker can exploit this vulnerability via an email message containing a crafted calendar header, leading to the execution of arbitrary JavaScript code.

EPSS — Exploit Probability

32.4%

Higher than 96.8% of all CVEs

Required Action

https://wiki.zimbra.com/wiki/Zimbra_Releases/8.8.15/P46#Security_Fixes ; https://wiki.zimbra.com/wiki/Zimbra_Releases/9.0.0/P39#Security_Fixes ; https://wiki.zimbra.com/wiki/Zimbra_Releases/10.0.7#Security_Fixes ; https://nvd.nist.gov/vuln/detail/CVE-2024-27443

Risk Assessment

ELEVATED

In CISA KEV

Details

Severity: High
EPSS: 32.4%
CISA KEV: Yes
Ransomware: Unknown
Articles: 0

Timeline

Published

May 19, 2025

Added to KEV

May 19, 2025

Remediation Due

Jun 9, 2025

Affected Product

Synacor

Zimbra Collaboration Suite (ZCS)

View all Synacor CVEs

External Links

NVD (NIST)CVE Details MITRE CVE