CVE-2023-34192
Critical 9.0 Exploited in the wild (KEV)
Confirmed active exploitation — CISA KEV catalog
- Name
- Synacor Zimbra Collaboration Suite (ZCS) Cross-Site Scripting (XSS) Vulnerability
- Added to catalog
- Remediation due date (US federal)
- Required action
- Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Description
Cross Site Scripting vulnerability in Zimbra ZCS v.8.8.15 allows a remote authenticated attacker to execute arbitrary code via a crafted script to the /h/autoSaveDraft function.
Metrics
- CVSS 3.1
-
9.0 (CRITICAL)
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H - EPSS — exploit probability
- 77% (percentile: 100) as of 2 November 2026
- CWE
- CWE-79
Affected products
synacor: zimbra collaboration suite
References
- https://wiki.zimbra.com/wiki/Security_Center Release NotesVendor Advisory
- https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories Vendor Advisory
- https://wiki.zimbra.com/wiki/Security_Center Release NotesVendor Advisory
- https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories Vendor Advisory
- https://wiki.zimbra.com/wiki/Zimbra_Responsible_Disclosure_Policy Not Applicable
- https://wiki.zimbra.com/wiki/Zimbra_Responsible_Disclosure_Policy Not Applicable
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023… US Government Resource