CVE-2025-66376

Zimbra Collaboration (ZCS) 10 before 10.0.18 and 10.1 before 10.1.13 allows Classic UI stored XSS via Cascading Style Sheets (CSS) @import directives in an HTML e-mail message.

CVSS v3 7.2 HIGH

7.2^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://wiki.zimbra.com/wiki/Security_Center	Release Notes Vendor Advisory
https://wiki.zimbra.com/wiki/Zimbra_Releases/10.0.18#Security_Fixes	Release Notes
https://wiki.zimbra.com/wiki/Zimbra_Releases/10.1.13#Security_Fixes	Release Notes
https://wiki.zimbra.com/wiki/Zimbra_Responsible_Disclosure_Policy	Product
https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories	Vendor Advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-66376	US Government Resource

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:synacor:zimbra_collaboration_suite::::::::
	cpe:2.3:a:synacor:zimbra_collaboration_suite::::::::

History

30 Sep 2026, 23:10

Type	Values Removed	Values Added
Summary		(es) Zimbra Collaboration (ZCS) 10 anterior a 10.0.18 y 10.1 anterior a 10.1.13 permite XSS almacenado en la interfaz de usuario clásica a través de directivas @import de Hojas de Estilo en Cascada (CSS) en un mensaje de correo electrónico HTML.

Information

Published : 2026-01-05 15:15

Updated : 2026-10-07 10:10

NVD link : CVE-2025-66376

Mitre link : CVE-2025-66376

CVE.ORG link : CVE-2025-66376

JSON object : View

Products Affected

synacor

zimbra_collaboration_suite

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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