CVE-2025-48700

synacor zimbra collaboration suite

Published 23 Jun 2025 · updated 17 Jun 2026 · Analyzed

6.1 Medium · CVSS 3.1, CISA ADP

Exploited in the wild

CISA added this to its Known Exploited Vulnerabilities catalog on 20 Apr 2026, with a remediation deadline of 23 Apr 2026 for US federal agencies.

Required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Description

An issue was discovered in Zimbra Collaboration (ZCS) 8.8.15 and 9.0 and 10.0 and 10.1. A Cross-Site Scripting (XSS) vulnerability in the Zimbra Classic UI allows attackers to execute arbitrary JavaScript within the user's session, potentially leading to unauthorized access to sensitive information. This issue arises from insufficient sanitization of HTML content, specifically involving crafted tag structures and attribute values that include an @import directive and other script injection vectors. The vulnerability is triggered when a user views a crafted e-mail message in the Classic UI, requiring no additional user interaction.

References