Vulnerability details
CVE-2025-66376
Actively exploited
Zimbra Collaboration
CVSS 3.1
7.2High
Official 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.
CVSS scores
| Score | Version | Source | Vector |
|---|---|---|---|
| 7.2High | 3.1 | CVEProject cvelistV5 (CNA) (mitre) | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N |
Affected products
| Vendor | Product | Versions | Source |
|---|---|---|---|
| Zimbra | Collaboration | 10.0 ≤ v < 10.0.18 | CVEProject cvelistV5 (CNA) |
| Zimbra | Collaboration | 10.1 ≤ v < 10.1.13 | CVEProject cvelistV5 (CNA) |
References and advisories
6- https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories
- https://wiki.zimbra.com/wiki/Security_Center
- https://wiki.zimbra.com/wiki/Zimbra_Responsible_Disclosure_Policy
- https://wiki.zimbra.com/wiki/Zimbra_Releases/10.1.13#Security_Fixes
- https://wiki.zimbra.com/wiki/Zimbra_Releases/10.0.18#Security_Fixes
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-66376 government-resource
Kolun on Telegram @kolunsec
Exploited CVEs, key news and a daily digest
Alerts for this product's next CVEsFollow the product to get new vulnerabilities on Telegram.
Details
- Published
- 2026-01-05
- Last updated
- 2026-03-19
- State
- Published
- Assigner (CNA)
- mitre
- Kolun priority
- 85 · Critical
CISA KEV catalog
- Date added
- 2026-03-18
- Due date
- 2026-04-01
- Used in ransomware
- Unknown
Exploit prediction (EPSS)
20.22%
Probability of exploitation in 30 days
97.4%
Percentile (among all CVEs)
SSVC assessment (CISA)
- Automatable
- No
- Exploitation
- Active
- Technical impact
- Partial
Weaknesses (CWE)
- CWE-79Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting')