CVE-2025-48700 — Synacor Zimbra Collaboration Suite (ZCS) Cross-site Scripting Vulnerability
CVE-2025-48700: Synacor Zimbra Collaboration Suite (ZCS) Cross-site Scripting Vulnerability
CISA Known Exploited Vulnerability (KEV)
| Vendor / project | Synacor |
| Product | Zimbra Collaboration Suite (ZCS) |
| Date added | 2026-04-20 |
| Due date | 2026-04-23 |
| Ransomware campaign use | Unknown |
Description
Synacor Zimbra Collaboration Suite (ZCS) contains a cross-site scripting vulnerability that could allow attackers to execute arbitrary JavaScript within the user's session, potentially leading to unauthorized access to sensitive information.
Required action (CISA)
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Notes
https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories ; https://nvd.nist.gov/vuln/detail/CVE-2025-48700
References
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-48700
- KEV catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog