CVE-2025-48700
Synacor Zimbra Collaboration Suite (ZCS) Cross-site Scripting Vulnerability
This vulnerability is in the CISA Known Exploited Vulnerabilities catalog: attackers are using it. If you run Zimbra Collaboration Suite (ZCS), fix it now.
CISA 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.
US federal civilian agencies must remediate by Apr 23, 2026.
Patch status
No official fix confirmed yet
Until a fix ships, follow the vendor's mitigations and CISA's required action, limit exposure of affected systems, and watch this record for a patch.
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.
Source: NIST National Vulnerability Database. Official vulnerability data, reproduced as published.
Affected products
| Product | Vendor | Affected versions | Fixed in | Source |
|---|---|---|---|---|
| Zimbra Collaboration Suite | Synacor | >= 10.0.0, < 10.0.12; >= 10.1.0, < 10.1.4; 8.8.15; 9.0.0 | 10.0.12; 10.1.4 | NVD |
| Zimbra Collaboration Suite (ZCS) | Synacor | — | — | KEV |
Sources: NVD = NIST National Vulnerability Database; KEV = CISA Known Exploited Vulnerabilities catalog.
Intelligence timeline
Developments from the last 30 days, newest first.
No developments recorded for CVE-2025-48700 in the last 30 days.
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Coverage
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