01 Record
CVE-2025-66376
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.
HighKEVPUBLISHEDCNA: mitre
CNA base score7.2 CVSS v3.xCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
02 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.
03 Exploitation and scoring
- Exploitation
- Exploited in the wild. Listed in the CISA Known Exploited Vulnerabilities catalog on 2026-03-18. Federal remediation due 2026-04-01.
- SSVC decision
- ExploitationactiveCISA reports credible evidence of active exploitation.
- AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
- Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.
- EPSS probability
- 20.22% probability of exploitation activity in the next 30 days.
- EPSS percentile
- Equal to or higher than the score of 97.4% of scored records. A rank, not a probability.
- NVD base score
- 6.1 (CVSS v3.x), scored by the NVD independently of the CNA.
- NVD CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
- NVD analysis status
- Analyzed. NVD last modified this record on 2026-10-07.
- Red Hat severity
- No Red Hat rating. Red Hat rates the CVEs that affect its products.
Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.
04 Metadata
- Published
- 2026-01-05 00:00Z9 MO AGO
- Last updated
- 2026-03-19 03:55Z7 MO AGO
- Reserved
- 2025-11-28
- Assigning CNA
- mitre
- Record state
- PUBLISHED
- Severity
- High (CVSS 7.2)
- CNA CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
- Weaknesses
- CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')Base
- Data version
- 5.2
- Document digest
- 896726fc815f363cd0679c60732bcae9b573646f3f9f4350cd70526e7ab5f4d7
05 Affected products
VendorProductVersionsPlatforms
06 References
- wiki.zimbra.comhttps://wiki.zimbra.com/wiki/Zimbra_Security_Advisories
- wiki.zimbra.comhttps://wiki.zimbra.com/wiki/Security_Center
- wiki.zimbra.comhttps://wiki.zimbra.com/wiki/Zimbra_Responsible_Disclosure_Policy
- wiki.zimbra.comhttps://wiki.zimbra.com/wiki/Zimbra_Releases/10.1.13#Security_Fixes
- wiki.zimbra.comhttps://wiki.zimbra.com/wiki/Zimbra_Releases/10.0.18#Security_Fixes
- www.cisa.govhttps://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-66376