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ShardingsphereApplication · Apache

CVE-2020-1947

CRITICAL · 9.8 CVSS v3.1 Published 2020-03-11
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
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
In Apache ShardingSphere(incubator) 4.0.0-RC3 and 4.0.0, the ShardingSphere's web console uses the SnakeYAML library for parsing YAML inputs to load datasource configuration. SnakeYAML allows to unmarshal data to a Java type By using the YAML tag. Unmarshalling untrusted data can lead to security flaws of RCE.

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

Apache ShardingSphere's web console uses SnakeYAML to parse YAML datasource configurations. The library's default behavior allows deserialization of arbitrary Java objects via YAML tags (e.g., !!javax.script.ScriptEngineManager), enabling unauthenticated remote code execution by crafting malicious YAML payloads.

MitigationUpgrade to a patched version of Apache ShardingSphere that addresses this vulnerability, or implement a SafeConstructor to restrict YAML deserialization to safe types only.

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
ShardingsphereApplication
Affected:= 4.0.0

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
High

CVSS:3.1/AV:N/AC:L/PR:N/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 Apache ShardingSphere installation and version
    Locate ShardingSphere installation directory and check the version. Common paths include /opt/shardingsphere or check for shardingsphere-*.jar files. Read the version from the jar filename, README, or version.properties file.
    Affected if The installed version is exactly 4.0.0
  2. Verify web console is enabled
    Check the ShardingSphere configuration files (such as application.yml or server.yaml in the conf directory) for web console settings. Look for 'shardingsphere-ui' or 'web' related configurations that enable the admin console.
    Affected if The web console (shardingsphere-ui) is enabled and accessible on a network-reachable port
  3. Check datasource configuration capability
    Identify if the YAML datasource configuration feature is exposed. Review the web console's API endpoints or configuration UI that accepts YAML input for datasource definitions.
    Affected if The YAML datasource configuration feature is accessible via the web console without additional authentication or with default credentials
  4. Confirm SnakeYAML library is in use
    Examine the ShardingSphere lib or classpath for the presence of snakeyaml.jar. Check the application's dependency tree or lib directory for SnakeYAML library files.
    Affected if The SnakeYAML library is present in the ShardingSphere installation

Your environment is affected if Apache ShardingSphere version 4.0.0 is installed with the web console enabled and the YAML datasource configuration feature accessible, since the default SnakeYAML parser allows arbitrary object deserialization.

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
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Upgrade to a patched version of Apache ShardingSphere that addresses this vulnerability, or implement a SafeConstructor to restrict YAML deserialization to safe types only.

Recommended fix High confidence

Apache ShardingSphere 4.0.1

  1. 1. Back up your current ShardingSphere configuration and data
  2. 2. Download Apache ShardingSphere version 4.0.1 or later from the official Apache release repository
  3. 3. Stop the ShardingSphere web console service
  4. 4. Replace the ShardingSphere 4.0.0 installation with version 4.0.1
  5. 5. Restore your configuration from the backup
  6. 6. Start the ShardingSphere service
  7. 7. Verify the web console is operational and the YAML datasource configuration loads correctly
Caveat Review release notes for any configuration or feature changes between 4.0.0 and 4.0.1

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

Fix this in Shardingsphere Scoped from the published advisory
  • Consultation3.0 h
  • Implementation6.0 h
  • Testing6.0 h
  • Review / QA3.0 h
18.0 hours of engineering $3,120
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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-2020-1947 in production — separate from our analysis above.

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What this is

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What belongs here
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  • Version or environment caveats, and links to real fixes
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