Synacor Zimbra Collaboration ProxyServlet server-side request forgery

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.2$0-$5k0.00

Summaryinfo

A vulnerability classified as critical has been found in Synacor Zimbra Collaboration up to 8.6 Patch 12/8.7.11 Patch 9/8.8.10 Patch 6/8.8.11 Patch 2. Affected by this issue is some unknown functionality of the component ProxyServlet. This manipulation causes server-side request forgery. This vulnerability is registered as CVE-2019-9621. Remote exploitation of the attack is possible. Furthermore, an exploit is available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical was found in Synacor Zimbra Collaboration up to 8.6 Patch 12/8.7.11 Patch 9/8.8.10 Patch 6/8.8.11 Patch 2 (Groupware Software). Affected by this vulnerability is some unknown processing of the component ProxyServlet. The manipulation with an unknown input leads to a server-side request forgery vulnerability. The CWE definition for the vulnerability is CWE-918. The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

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.

The bug was discovered 04/11/2019. The weakness was published 04/30/2019 as EDB-ID 46693 as not defined exploit (Exploit-DB). The advisory is shared at exploit-db.com. This vulnerability is known as CVE-2019-9621 since 03/06/2019. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details are unknown but a public exploit is available.

After immediately, there has been an exploit disclosed. It is possible to download the exploit at exploit-db.com. It is declared as attacked. The vulnerability was handled as a non-public zero-day exploit for at least 19 days. During that time the estimated underground price was around $0-$5k. The vulnerability scanner Nessus provides a plugin with the ID 241987 (Zimbra Collaboration Server < 8.7.11 Patch 11, 8.8 < 8.8.9 Patch 10, 8.8.10 < Patch 8, 8.8.11 < Patch 4), which helps to determine the existence of the flaw in a target environment. The CISA Known Exploited Vulnerabilities Catalog lists this issue since 07/07/2025 with a due date of 07/28/2025:

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Upgrading to version 8.6 Patch 13, 8.7.11 Patch 10, 8.8.10 Patch 7 or 8.8.11 Patch 3 eliminates this vulnerability.

The vulnerability is also documented in the databases at Exploit-DB (46693) and Tenable (241987). Similar entry is available at VDB-135716. If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.4
VulDB Meta Temp Score: 7.2

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔍

CVSSv2info

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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Server-side request forgery
CWE: CWE-918
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Attacked
Download: 🔍

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EPSS Percentile: 🔍

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KEV Due: 🔍
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KEV Ransomware: 🔍
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Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 241987
Nessus Name: Zimbra Collaboration Server < 8.7.11 Patch 11, 8.8 < 8.8.9 Patch 10, 8.8.10 < Patch 8, 8.8.11 < Patch 4

Exploit-DB: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍
Exploit Delay Time: 🔍

Upgrade: Zimbra Collaboration 8.6 Patch 13/8.7.11 Patch 10/8.8.10 Patch 7/8.8.11 Patch 3

Timelineinfo

03/06/2019 🔍
04/11/2019 +36 days 🔍
04/30/2019 +19 days 🔍
04/30/2019 +0 days 🔍
04/30/2019 +0 days 🔍
04/30/2019 +0 days 🔍
07/12/2025 +2264 days 🔍

Sourcesinfo

Vendor: synacor.com

Advisory: EDB-ID 46693
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2019-9621 (🔍)
GCVE (CVE): GCVE-0-2019-9621
GCVE (VulDB): GCVE-100-134245
scip Labs: https://www.scip.ch/en/?labs.20161013
See also: 🔍

Entryinfo

Created: 04/30/2019 23:12
Updated: 07/12/2025 01:49
Changes: 04/30/2019 23:12 (68), 06/05/2020 08:27 (1), 06/26/2024 12:20 (17), 07/07/2025 23:15 (18), 07/07/2025 23:24 (2), 07/12/2025 01:49 (2)
Complete: 🔍
Cache ID: 216::103

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