How severe is CVE-2016-3406?

CVE-2016-3406 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2016-3406 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (56th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-3406?

CVE-2016-3406 affects Synacor Zimbra Collaboration Suite. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2016-3406?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2016-3406 published?

CVE-2016-3406 was published on 2017-01-18 and last updated on 2026-06-17.

CVE-2016-3406

CVE-2016-3406 is a high-severity vulnerability in Synacor Zimbra Collaboration Suite with a CVSS 3.x base score of 8.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-352.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.8
EPSS exploit prediction: 1% (56th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-352
Affected product: Synacor Zimbra Collaboration Suite
Published: 2017-01-18
Last modified: 2026-06-17

Description

Multiple cross-site request forgery (CSRF) vulnerabilities in Zimbra Collaboration before 8.7.0 allow remote attackers to hijack the authentication of unspecified victims via vectors involving (1) the Client uploader extension or (2) extension REST handlers, aka bugs 104294 and 104456.

Frequently asked questions

What is CVE-2016-3406?: Multiple cross-site request forgery (CSRF) vulnerabilities in Zimbra Collaboration before 8.7.0 allow remote attackers to hijack the authentication of unspecified victims via vectors involving (1) the Client uploader extension or (2) extension REST handlers, aka bugs 104294 and 104456.
How severe is CVE-2016-3406?: CVE-2016-3406 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2016-3406 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (56th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-3406?: CVE-2016-3406 affects Synacor Zimbra Collaboration Suite. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2016-3406?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2016-3406 published?: CVE-2016-3406 was published on 2017-01-18 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:synacor:zimbra_collaboration_suite:*:*:*:*:*:*:*:*

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