How severe is CVE-2019-9670?

CVE-2019-9670 has a CVSS score of 9.8/10, rated CRITICAL. Immediate patching is strongly recommended.

Which packages are affected by CVE-2019-9670?

Affected package information for CVE-2019-9670 is not yet fully mapped. Check the official advisory links for details.

How do I fix CVE-2019-9670?

No fixed version has been published for CVE-2019-9670 yet. Monitor the advisory for updates, apply mitigations recommended by the vendor, and use O3 Security to track when a fix becomes available in your stack.

Is CVE-2019-9670 actively exploited in the wild?

Yes. There are 12 known exploit references for CVE-2019-9670, including 1 documented proof-of-concept exploit on Exploit-DB and 10 in-the-wild exploitations observed on GitHub and other sources. Treat this as actively exploitable and prioritize patching immediately. All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

What is the EPSS score for CVE-2019-9670?

CVE-2019-9670 has an EPSS (Exploit Prediction Scoring System) score of 94.4%, placing it in the 100th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. A score above 50% indicates significantly elevated exploitation risk — immediate patching is strongly recommended.

Is CVE-2019-9670 in the CISA Known Exploited Vulnerabilities catalog?

Yes. CVE-2019-9670 (Synacor Zimbra Collaboration Suite (ZCS) Improper Restriction of XML External Entity Reference) was added to CISA's Known Exploited Vulnerabilities (KEV) catalog on 2022-01-10. CISA required all US federal civilian agencies to remediate this vulnerability by 2022-07-10. The required action was: Apply updates per vendor instructions. Being listed in the KEV catalog is the strongest possible confirmation of active exploitation — treat this as a critical priority.

What type of vulnerability is CVE-2019-9670?

CVE-2019-9670 is classified as XML External Entity (XXE) (CWE-611). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

Is there exploit tooling available for CVE-2019-9670?

A Nuclei detection template exists for CVE-2019-9670, meaning automated scanners can fingerprint it. Public exploit tooling significantly increases real-world risk — prioritize patching and ensure detection coverage. Exploit tooling should only ever be used in isolated, authorized testing environments.

When was CVE-2019-9670 published, and has it been updated?

CVE-2019-9670 was published on May 29, 2019 and was last updated on April 10, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

CISA KEV·Added 2022-01-10 — agencies required to remediate by 2022-07-10

CVE-2019-9670

CRITICAL

Published

May 29, 2019

Updated

Apr 10, 2026

Affected

0 pkgs

Patched

None yet

Exploits

12 known

EPSS Exploitation Probability

via FIRST.org ↗

94.4%probability of exploitation in next 30 days

Very High Risk100th percentile0.00%

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Description

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.

Exploits & PoCs

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

EDB-46693remotelinux✓ Verified

Zimbra Collaboration - Autodiscover Servlet XXE and ProxyServlet SSRF (Metasploit)

by Metasploit · Apr 12, 2019

Exploit-DB Source

Frequently Asked Questions

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.

O3 Security · Impact-Aware SCA

Is CVE-2019-9670 in your stack?

O3 detects CVE-2019-9670 across dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

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