CVE-2024-27443

Description

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.

Scoring

• CVSS: 6.1 (MEDIUM, 3.1)
• EPSS exploitation probability: Not yet available
• EPSS percentile: Not yet available

CISA KEV status

• Added to KEV: 2025-05-19
• Remediation due date: 2025-06-09
• Known ransomware campaign use: Unknown

Weakness types (CWE)

• CWE-79
• CWE-79

References

• https://wiki.zimbra.com/wiki/Zimbra_Releases/10.0.7#Security_Fixes
• https://wiki.zimbra.com/wiki/Zimbra_Releases/9.0.0/P39#Security_Fixes
• https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2024-27443
• https://www.welivesecurity.com/en/eset-research/operation-roundpress/

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