CVE-2019-9621
HighExploitedPublic exploitZimbra 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.
Published Apr 30, 2019 · Updated Jul 8, 2026
Key Facts
Patch immediately- CVE-2019-9621 is a high-severity vulnerability (CVSS 7.5 v3.1) affecting Zimbra Collaboration Suite (Synacor).
- It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Sep 18, 2023. Public exploit code is available.
- EPSS estimates a 81% probability of exploitation in the next 30 days.
- Fixed versions are available, including Zimbra Collaboration Suite 8.6.0.
- Brandefense priority: patch immediately, because it is listed as exploited in the wild.
CVSS v3.1
7.5
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
EPSS (30-day exploit likelihood)
81%
Higher than 99.6% of all scored CVEs
Exploited in the wild
Yes
4 catalog listings
Public exploit code
Available
Proof-of-concept or weaponized module
Get the full CVE-2019-9621 brief as a PDF
Every affected product and fixed release, exploitation status and a first 24 hours response checklist, emailed within minutes.
Description
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.
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| CISA KEV | Jul 7, 2025 | Jul 28, 2025 | Not reported |
| Industry KEV feed | Sep 18, 2023 | Jul 28, 2025 | Not reported |
| CIRCL KEV | Jul 7, 2025 | Jul 28, 2025 | Not reported |
| ENISA EUVD | Jul 7, 2025 | n/a | Not reported |
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.
Affected Products
46 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| Zimbra Collaboration SuiteSynacor | 8.6.0, 8.6.0-patch1, 8.6.0-patch10, 8.6.0-patch11, 8.6.0-patch12, 8.6.0-patch2, 8.6.0-patch3, 8.6.0-patch4 | 8.6.0 |
Patched Releases
Zimbra Collaboration Suite
8.6.0
Timeline
Publicly disclosed
Apr 30, 2019
Added to Industry KEV feed
Sep 18, 2023
Added to CISA KEV
Jul 7, 2025
Added to CIRCL KEV
Jul 7, 2025
Added to ENISA EUVD
Jul 7, 2025
Last updated
Jul 8, 2026
Weakness Type
- CWE-918 Server-Side Request Forgery (SSRF)
References
- advisoryhttps://blog.tint0.com/2019/03/a-saga-of-code-executions-on-zimbra.html
- advisoryhttps://blog.zimbra.com/2019/03/9826/
- advisoryhttps://wiki.zimbra.com/wiki/Security_Center
- advisoryhttps://wiki.zimbra.com/wiki/Zimbra_Security_Advisories
- exploithttp://packetstormsecurity.com/files/152487/Zimbra-Collaboration-Autodiscover-Servlet-XXE-ProxyServlet-SSRF.html
FAQ
Common Questions.
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.
Affected: Zimbra Collaboration Suite (Synacor) versions 8.6.0, 8.6.0-patch1, 8.6.0-patch10, 8.6.0-patch11, 8.6.0-patch12, 8.6.0-patch2, 8.6.0-patch3, 8.6.0-patch4. The full list is in the CVE brief.
It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Sep 18, 2023.
Yes. It was added on Jul 7, 2025 with a federal remediation due date of Jul 28, 2025.
Public exploit code is available.
Fixed versions are available, including Zimbra Collaboration Suite 8.6.0.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
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