Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HSummary
CVE-2019-9670 is a critical-severity Improper Restriction of XML External Entity Reference (CWE-611) 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 0.0% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog; a public proof-of-concept is referenced.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
The vulnerability is an XML External Entity injection (XXE) flaw, tracked as CWE-611, affecting the mailboxd component in Synacor Zimbra Collaboration Suite versions 8.7.x prior to 8.7.11p10. It is demonstrated through the Autodiscover/Autodiscover.xml endpoint and carries a CVSS 3.1 base score of 9.8.
An unauthenticated attacker with network access can supply malicious XML to the Autodiscover servlet, enabling arbitrary file disclosure, server-side request forgery, or further code execution on the affected server. Public exploit code and a Metasploit module have been published that chain the XXE into remote command execution.
Zimbra security advisories and the associated bug report direct administrators to upgrade to version 8.7.11p10 or later; the SANS Internet Storm Center diary also references the vendor patch as the primary remediation.
Public exploit modules and detailed technical write-ups appeared shortly after disclosure, confirming that the issue is readily exploitable in default installations.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2019-19036
Vulnerability Data
mailboxd component in Synacor Zimbra Collaboration Suite 8.7.x before 8.7.11p10 has an XML External Entity injection (XXE) vulnerability, as demonstrated by Autodiscover/Autodiscover.xml.
- CWE(s)
- KEV Date Added
- 10 January 2022
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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V1.5.1V15.3.2
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.
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.
Hardened XML parser configurations directly disable external entity resolution.
Secure SDLC practices include input validation and safe XML parser configuration that prevent XXE.
Vulnerability scanning can discover XXE flaws but does not prevent their introduction in code.
Patching eliminates XXE-vulnerable parser versions but is only one aspect of software maintenance.
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.
Security testing in development catches XXE via static analysis and dynamic XML fuzzing.
Vulnerability management identifies and patches XML libraries with unsafe default entity settings.
Secure development life cycle mandates input validation and entity handling that directly prevents XXE.
Application security requirements explicitly call for disabling external entity processing in XML parsers.
Secure architecture principles include safe parser configuration that mitigates external entity risks.
Secure coding standards require disabling DTDs and external entities in XML processing.