CVE-2023-34192
Synacor Zimbra Collaboration Suite (ZCS) Cross-Site Scripting (XSS) Vulnerability
Does this matter?
Known to be exploited in the wild (CISA KEV, CISA remediation deadline 18 March 2025). Treat as an emergency change: patch or isolate now, then hunt for prior compromise.
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.
- CVSS 3.1
- 9.0 CRITICALCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H
- EPSS
- 77.27% probability · 100th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Listed 25 February 2025 · due 18 March 2025
- Weakness
- CWE-79
- Affected
- synacor/zimbra collaboration suite
- Source
- cve@mitre.org
EPSS 77.3% since 30 October 2026; no change recorded yet. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
CISA notes
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories ; https://nvd.nist.gov/vuln/detail/CVE-2023-34192
References
- https://wiki.zimbra.com/wiki/Security_CenterRelease Notes, Vendor Advisory
- https://wiki.zimbra.com/wiki/Zimbra_Responsible_Disclosure_PolicyNot Applicable
- https://wiki.zimbra.com/wiki/Zimbra_Security_AdvisoriesVendor Advisory
- https://wiki.zimbra.com/wiki/Security_CenterRelease Notes, Vendor Advisory
- https://wiki.zimbra.com/wiki/Zimbra_Responsible_Disclosure_PolicyNot Applicable
- https://wiki.zimbra.com/wiki/Zimbra_Security_AdvisoriesVendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-34192US Government Resource
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.