CVE-2025-66376
Last modified
CVE-2025-66376 is a medium-severity vulnerability rated 6.1/10 on the CVSS scale. 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.. CISA has confirmed active exploitation in the wild. EPSS estimates a 12.01% chance of exploitation in the next 30 days.
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.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Exploitation Status
This vulnerability is listed in CISA’s Known Exploited Vulnerabilities catalog, confirming active exploitation in the wild. Federal agencies must remediate by .
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Synacor | Zimbra Collaboration Suite | >= 10.0.0, < 10.0.18 |
| Synacor | Zimbra Collaboration Suite | >= 10.1.0, < 10.1.13 |
References
- https://wiki.zimbra.com/wiki/Security_CenterRelease Notes, Vendor Advisory
- https://wiki.zimbra.com/wiki/Zimbra_Security_AdvisoriesVendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-66376US Government Resource
Timeline
- Published
- Last Modified
- Status
- Analyzed
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