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GemfireApplication · VMware

CVE-2020-5396

HIGH · 8.8 CVSS v3.1 Published 2020-07-31
Fix available
A fix is available. Upgrade to 1.10.2 / 1.11.1 or later.
See remediation →
94/100
Remediation priority · Urgent
Remotely reachable 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
VMware GemFire versions prior to 9.10.0, 9.9.2, 9.8.7, and 9.7.6, and VMware Tanzu GemFire for VMs versions prior to 1.11.1 and 1.10.2, when deployed without a SecurityManager, contain a JMX service available which contains an insecure default configuration. This allows a malicious user to create an MLet mbean leading to remote code execution.

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 · high confidence

VMware GemFire contains a JMX service with an insecure default configuration when deployed without a SecurityManager. This allows a remote attacker to create an MLet MBean, which can load and execute arbitrary Java code from remote URLs, leading to remote code execution.

MitigationEnable and properly configure a SecurityManager in GemFire deployments, and upgrade to a patched version (9.10.0+, 9.9.2+, 9.8.7+, 9.7.6+, Tanzu 1.11.1+, or 1.10.2+).

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
GemfireApplication
Affected:>= 9.7.0, < 9.7.6>= 9.8.0, < 9.8.7>= 9.9.0, < 9.9.2
Tanzu Gemfire For Virtual MachinesApplication
Affected:>= 1.10.0, < 1.10.2>= 1.11.0, < 1.11.1

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
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

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. Identify GemFire product and version
    Run 'gfsh version' or check the product installation manifest. For Tanzu GemFire, check the installed package version via the Operations Manager or run 'pivotal-cloud-cache cache-server version' if available.
    Affected if The installed version falls within: GemFire 9.7.0-9.7.5, 9.8.0-9.8.6, 9.9.0-9.9.1 OR Tanzu GemFire 1.10.0-1.10.1, 1.11.0-1.11.0.
  2. Locate GemFire configuration files
    Find gemfire.properties and cache.xml in the GemFire deployment directory, typically under the conf or config subdirectory of the installation root.
    Affected if Configuration files exist in the deployment.
  3. Verify if JMX manager is enabled
    Inspect gemfire.properties for 'jmx-manager' and 'jmx-manager-port' settings. Check if jmx-manager is set to 'true' or if the default JMX service is listening on the standard port (1099) or custom port.
    Affected if JMX manager is enabled and accessible on a network-exposed port.
  4. Confirm SecurityManager is not configured
    Search gemfire.properties for the 'security-manager' property. If absent, or if it is present but commented out, the SecurityManager is not active. Also verify no Java security policy file is being passed via JVM arguments.
    Affected if The 'security-manager' property is missing, commented out, or no security-manager-related JVM arguments are present in startup scripts.
  5. Check for MLet MBean exposure
    Use a JMX client tool (like jconsole or jmxterm) to connect to the JMX endpoint. Attempt to access the MBean domain 'javax.management.remote' or list MBeans containing 'MLet' in the name. If listing succeeds without authentication, the MLet MBean is exposed.
    Affected if The MLet MBean is accessible remotely without authentication.

You are affected if your GemFire version is in the vulnerable range AND JMX is enabled AND no SecurityManager is configured, making the MLet MBean remotely accessible for arbitrary code execution.

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.

From vendor data
Upgrade available Upgrade to 1.10.2 / 1.11.1 / 9.7.6 or later
Fixed in 1.10.21.11.19.7.6
Interim mitigation

Enable and properly configure a SecurityManager in GemFire deployments, and upgrade to a patched version (9.10.0+, 9.9.2+, 9.8.7+, 9.7.6+, Tanzu 1.11.1+, or 1.10.2+).

Fix this in Gemfire Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing6.0 h
  • Review / QA3.0 h
21.0 hours of engineering $3,680
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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-2020-5396 in production — separate from our analysis above.

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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