CVE-2025-48700

MEDIUM6.1Published on June 23, 2025

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.

Actively exploited

In the CISA exploited-vulnerabilities catalogue since Apr 20, 2026
US federal agencies must remediate it by Apr 23, 2026 (BOD 22-01)
First attack observed 300 days after disclosure

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

Source: CISA KEV · Jun 9, 2026 Apr 20, 2026

CVSS score6.1 / 10CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Weakness type (CWE)CWE-79

Vendorssynacor