Zimbra Collaboration SuiteApplication · Synacor

CVE-2016-3415

CRITICAL · 9.1 CVSS v3.0 Published 2017-01-18
Fix available
A fix is available. Upgrade to after 8.6.0 or later.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
Zimbra Collaboration before 8.7.0 allows remote attackers to conduct deserialization attacks via unspecified vectors, aka bug 102276.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

Zimbra Collaboration before version 8.7.0 contains a deserialization vulnerability (CWE-502) that allows remote unauthenticated attackers to execute arbitrary code via crafted serialized Java objects. The unspecified attack vectors likely involve network-exposed Zimbra services that handle serialized data without proper validation.

MitigationUpgrade Zimbra Collaboration to version 8.7.0 or later to remediate this vulnerability. If immediate patching is not possible, consider network segmentation and restricting access to Zimbra services from untrusted networks.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Zimbra Collaboration SuiteApplication
Affected:<= 8.6.0

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
None

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Check if Zimbra Collaboration is installed
    Look for Zimbra installation directories (commonly /opt/zimbra or /usr/local/zimbra) or run 'ps aux | grep zimbra' to find running Zimbra processes
    Affected if Zimbra is not installed means not affected
  2. Identify the installed Zimbra version
    Run 'zmcontrol -v' or check the Zimbra version file in the installation directory if available
    Affected if Version returned is 8.6.0 or lower indicates the affected version range
  3. Verify the exact version number
    Compare the installed version against the affected range: versions 8.6.0 and below are vulnerable; version 8.7.0 and above are not
    Affected if Version is 8.6.0 or lower means the deserialization vulnerability is present
  4. Determine if network-exposed Zimbra services are accessible
    Check if Zimbra web services (port 80, 443, 7071) or other network services are listening on interfaces accessible from untrusted networks
    Affected if Network services are exposed to untrusted networks increases likelihood of exploitation for this remote unauthenticated attack vector

If Zimbra Collaboration version 8.6.0 or lower is installed and its network services are accessible, the environment is vulnerable to CVE-2016-3415.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to a release after 8.6.0
Interim mitigation

Upgrade Zimbra Collaboration to version 8.7.0 or later to remediate this vulnerability. If immediate patching is not possible, consider network segmentation and restricting access to Zimbra services from untrusted networks.

Recommended fix High confidence

Zimbra Collaboration Suite 8.7.0 or later

  1. Create a full backup of the Zimbra server including mail stores, configuration, and database
  2. Verify backup integrity before proceeding
  3. Check current Zimbra version with: zmcontrol -v
  4. Review Zimbra 8.7.0 release notes and upgrade documentation at wiki.zimbra.com for pre-upgrade requirements
  5. Stop Zimbra services with: zmcontrol stop
  6. Ensure the operating system meets the minimum requirements for Zimbra 8.7.0
  7. Download Zimbra 8.7.0 or later from official Zimbra repositories
  8. Run the Zimbra installer as the root user: ./install.sh
Caveat Major version upgrades may introduce configuration changes; review release notes for breaking changes in mail flow, new features, and deprecated functionality before upgrading

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Zimbra Collaboration Suite Scoped from the published advisory
  • Consultation4.0 h
  • Implementation16.0 h
  • Testing12.0 h
  • Review / QA4.0 h
36.0 hours of engineering $6,200
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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2016-3415 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2016-3415 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data