dbcve.org
JavaApplication · Kubernetes

CVE-2021-25738

MEDIUM · 6.7 CVSS v3.1 Published 2021-10-11
Fix available
A fix is available. Upgrade to 11.0.1 or later.
See remediation →
69/100
Remediation priority · Elevated
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
Loading specially-crafted yaml with the Kubernetes Java Client library can lead to 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

The Kubernetes Java Client library contains a YAML deserialization vulnerability where loading specially crafted YAML files can lead to arbitrary code execution. This is a deserialization flaw in the library's YAML parsing functionality that allows attackers to inject malicious payloads through untrusted YAML input.

MitigationUpgrade the Kubernetes Java Client library to the patched version. Avoid loading YAML from untrusted sources and implement input validation for any YAML files processed by the application.

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
JavaApplication
Affected:<= 9.0.2>= 10.0.0, <= 10.0.1>= 11.0.0, < 11.0.1

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
Local
Complexity
Low
Privileges
High
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:L/AC:L/PR:H/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 Kubernetes Java Client dependency
    Review project build files (pom.xml, build.gradle, or equivalent) and dependency management configurations to locate the io.kubernetes:client-java dependency and note its version
    Affected if The dependency version falls within <= 9.0.2, >= 10.0.0 and <= 10.0.1, or >= 11.0.0 and < 11.0.1
  2. Locate YAML parsing code
    Search source code for imports of YAML processing classes such as org.yaml.snakeyaml.Yaml, or usages of ObjectMapper with YAML annotations, particularly in areas handling external or user-supplied input
    Affected if YAML parsing code exists that processes input from untrusted or external sources
  3. Identify YAML input sources
    Trace the data flow of YAML files through the application: check file upload handlers, configuration loaders, API endpoints accepting YAML payloads, and any deserialization points
    Affected if The application loads YAML from sources outside the trusted deployment environment (user uploads, external APIs, untrusted network sources)
  4. Confirm SnakeYAML library presence
    Examine the full dependency tree (mvn dependency:tree or gradle dependencies) to determine if the SnakeYAML library is transitively included as a dependency of the Kubernetes Java Client
    Affected if SnakeYAML is present in the classpath and used by the Kubernetes Java Client for YAML processing

You are affected if your project uses Kubernetes Java Client version 9.0.2 or earlier, 10.0.0-10.0.1, or 11.0.0 AND your application processes YAML input from untrusted or external sources.

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 11.0.1 or later
Fixed in 11.0.1
Interim mitigation

Upgrade the Kubernetes Java Client library to the patched version. Avoid loading YAML from untrusted sources and implement input validation for any YAML files processed by the application.

Recommended fix High confidence

kubernetes-client-java version 11.0.1 or later

  1. Upgrade the Kubernetes Java Client library to version 11.0.1 or later in your Maven pom.xml or Gradle build file
  2. For Maven, update the dependency to: <groupId>io.kubernetes</groupId><artifactId>client-java</artifactId><version>11.0.1</version>
  3. For Gradle, update the dependency to: implementation 'io.kubernetes:client-java:11.0.1'
  4. Rebuild and redeploy your application

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

Fix this in Java Scoped from the published advisory
  • Consultation3.0 h
  • Implementation4.0 h
  • Testing4.0 h
  • Review / QA2.0 h
13.0 hours of engineering $2,280
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,648.

Scan for this in your stack

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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-2021-25738 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