CVE-2020-7796
SSRF in Synacor Zimbra Collaboration Suite ≤ 8.8.15
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HSummary
CVE-2020-7796 is a critical-severity SSRF (CWE-918) vulnerability in Synacor Zimbra Collaboration Suite. Its CVSS base score is 9.8 (Critical).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 0.3% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
Zimbra Collaboration Suite (ZCS) versions prior to 8.8.15 Patch 7 are affected by a server-side request forgery vulnerability (CWE-918) that manifests when the WebEx zimlet is installed and zimlet JSP functionality is enabled. The flaw carries a CVSS 3.1 score of 9.8, reflecting network-accessible attack vectors with low complexity and no required privileges or user interaction.
An unauthenticated remote attacker can supply crafted requests that cause the ZCS server to initiate arbitrary outbound connections, potentially reaching internal resources, exfiltrating data, or performing actions on the attacker’s behalf with the server’s privileges. Successful exploitation can result in full compromise of confidentiality, integrity, and availability of the affected system.
The official Zimbra 8.8.15 Patch 7 release notes document the fix for this issue. The vulnerability is also catalogued in CISA’s Known Exploited Vulnerabilities list, indicating confirmed in-the-wild exploitation.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2020-28728
Vulnerability Data
Zimbra Collaboration Suite (ZCS) before 8.8.15 Patch 7 allows SSRF when WebEx zimlet is installed and zimlet JSP is enabled.
- CWE(s)
- KEV Date Added
- 17 February 2026
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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V1.3.6V1.5.3V5.3.2V10.4.7
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Penetration testing attempts server-side requests to internal resources, identifying SSRF weaknesses for remediation.
Outbound connections to external resources can be monitored and limited at the boundary, reducing SSRF impact.
Validates server-side URLs and resource references to block SSRF attempts.
Detects server-side request forgery through monitoring of unexpected outbound connections.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Secure development practices directly include input validation and destination allow-listing that prevent SSRF.
Runtime monitoring of web applications and services can detect anomalous outbound requests indicative of SSRF.
Vulnerability identification processes can discover and record SSRF flaws in web applications.
Network segmentation and egress controls can limit the damage from successful SSRF requests.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Operational threat data describing SSRF campaigns can be used to tighten outbound-request allow-lists and detection rules before attackers exploit them.