CVE-2025-66376 KEV
7.2
HIGH · CVSS 3.1 · EPSS 19.6% (pctl 97)
Patch first
On CISA KEV — known exploited in the wild, due 2026-04-01.
Description
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.
Scoring
| CVSS | 7.2 (HIGH, v3.1) |
|---|---|
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N |
| EPSS | 19.56% — more likely to be exploited than 97% of all CVEs |
| Weakness | CWE-79 |
| On CISA KEV | yes — remediate by 2026-04-01 |
| Public exploit | none known |
| Published | 2026-01-05 |
| Last modified | 2026-06-17 |
CISA KEV
| Name | Synacor Zimbra Collaboration Suite (ZCS) Cross-Site Scripting Vulnerability |
|---|---|
| Added | 2026-03-18 |
| Due | 2026-04-01 |
| Vendor / product | Synacor / Zimbra Collaboration Suite (ZCS) |
| Ransomware use | none reported |
Affected (1)
| Vendor | Product |
|---|---|
| synacor | zimbra collaboration suite |
References
- https://wiki.zimbra.com/wiki/Security_Center
- https://wiki.zimbra.com/wiki/Zimbra_Releases/10.0.18#Security_Fixes
- https://wiki.zimbra.com/wiki/Zimbra_Releases/10.1.13#Security_Fixes
- https://wiki.zimbra.com/wiki/Zimbra_Responsible_Disclosure_Policy
- https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-66376
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