Assessment
Why it matters
CISA lists this vulnerability as known to be exploited; exploitation is confirmed; EPSS is 81.0%; technical severity is CVSS 7.5.
Zimbra Collaboration Suite before 8.6 patch 13, 8.7.x before 8.7.11 patch 10, and 8.8.x before 8.8.10 patch 7 or 8.8.x before 8.8.11 patch 3 allows SSRF via the ProxyServlet component.
Who should care
- Teams operating Zimbra Collaboration Suite, Zimbra Collaboration Suite (ZCS)
- Vulnerability and exposure management teams
- Security operations teams monitoring exploitation activity
Response plan
What I would do
- Confirm whether Zimbra Collaboration Suite, Zimbra Collaboration Suite (ZCS) is present in the environment.
- Identify affected versions and establish whether vulnerable services are exposed or reachable.
- Vendor advisory from blog.zimbra.com
- Review relevant security telemetry for evidence of attempted or successful exploitation.
- Document the remediation decision and track it to verified completion.
Treatment intelligence
Remediation intelligence
Vendor sources are listed before government and third-party guidance. Confirm product applicability and change prerequisites before deployment.
Verification noteAutomated link verification has not completed for this guidance yet.
Technical details
- CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
- CWE
- CWE-918
- Affected versions
- Synacor Zimbra Collaboration Suite (End Excluding 8.6.0 | Start Including 8.7.0, End Excluding 8.7.11 | Start Including 8.8.0, End Excluding 8.8.9 | Version 8.6.0); Synacor Zimbra Collaboration Suite (ZCS)
- Fixed versions
- Synacor Zimbra Collaboration Suite (Fixed from 8.6.0, 8.7.11, 8.8.9)
- Published
- 30 April 2019
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
Signal timeline
- CVE published
- Added to CISA KEV
- Latest EPSS score: 81.0%
- Signal calculated at 81
External references
- CISA Government advisory CVE-2019-9621
- Exploit information from packetstormsecurity.com
- Exploit information from packetstormsecurity.com
- Exploit information from www.rapid7.com
- Blog Tint0 Third-party advisory A Saga Of Code Executions On Zimbra
- Blog Zimbra Technical reference
- Bugzilla Zimbra Technical reference Show Bug.cgi
- Wiki Zimbra Technical reference Zimbra Security Advisories
- Exploit information from www.exploit-db.com