What is CVE-2018-1000210?

CVE-2018-1000210 is a high-severity insecure deserialization vulnerability in YamlDotNet (nuget), affecting versions <= 4.3.2. It is fixed in 5.0.0. Untrusted serialized data is processed by a deserializer that can instantiate arbitrary objects or execute code as a side effect.

How severe is CVE-2018-1000210?

CVE-2018-1000210 has a CVSS score of 7.8 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.

Which packages are affected by CVE-2018-1000210?

YamlDotNet (nuget) versions <= 4.3.2; YamlDotNet.Signed (nuget) versions <= 4.3.2.

Is there a fix for CVE-2018-1000210?

Yes. CVE-2018-1000210 is fixed in 5.0.0. Upgrade to this version or later.

Is CVE-2018-1000210 exploitable, and should I be worried?

Whether CVE-2018-1000210 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk.

What actually determines whether CVE-2018-1000210 is exploitable, and how bad it is?

Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.

CVE-2018-1000210 in YamlDotNet

Q: How severe is CVE-2018-1000210?

CVE-2018-1000210 has a CVSS score of 7.8 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.

Q: Which packages are affected by CVE-2018-1000210?

YamlDotNet (nuget) versions <= 4.3.2; YamlDotNet.Signed (nuget) versions <= 4.3.2.

Q: Is there a fix for CVE-2018-1000210?

Yes. CVE-2018-1000210 is fixed in 5.0.0. Upgrade to this version or later.

Q: Is CVE-2018-1000210 exploitable, and should I be worried?

Whether CVE-2018-1000210 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk.

Q: What actually determines whether CVE-2018-1000210 is exploitable, and how bad it is?

Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.

Q: How do I fix CVE-2018-1000210?

Upgrade: YamlDotNet to 5.0.0 or later, YamlDotNet.Signed to 5.0.0 or later.

Summary

High severity vulnerability that affects YamlDotNet and YamlDotNet.Signed

YamlDotNet version 4.3.2 and earlier contains a Insecure Direct Object Reference vulnerability in The default behavior of Deserializer.Deserialize() will deserialize user-controlled types in the line "currentType = Type.GetType(nodeEvent.Tag.Substring(1), throwOnError: false);" and blindly instantiates them. that can result in Code execution in the context of the running process. This attack appear to be exploitable via Victim must parse a specially-crafted YAML file. This vulnerability appears to have been fixed in 5.0.0.

Impact

Untrusted serialized data is processed by a deserializer that can instantiate arbitrary objects or execute code as a side effect. Typical impact: arbitrary code execution or logic abuse.

CVE-2018-1000210 has a CVSS score of 7.8 (High). The vector is requires local access, no privileges required, and user interaction required. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (5.0.0); upgrading removes the vulnerable code path.

Affected versions

YamlDotNet (<= 4.3.2) YamlDotNet.Signed (<= 4.3.2)

Security releases

YamlDotNet → 5.0.0 (nuget) YamlDotNet.Signed → 5.0.0 (nuget)

Kodem intelligence

Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.

Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.

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Remediation advice

Upgrade the following packages to resolve this vulnerability:

YamlDotNet to 5.0.0 or later; YamlDotNet.Signed to 5.0.0 or later

Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.

Frequently Asked Questions

What is CVE-2018-1000210? CVE-2018-1000210 is a high-severity insecure deserialization vulnerability in YamlDotNet (nuget), affecting versions <= 4.3.2. It is fixed in 5.0.0. Untrusted serialized data is processed by a deserializer that can instantiate arbitrary objects or execute code as a side effect.
How severe is CVE-2018-1000210? CVE-2018-1000210 has a CVSS score of 7.8 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
Which packages are affected by CVE-2018-1000210?
- YamlDotNet (nuget) (versions <= 4.3.2)
- YamlDotNet.Signed (nuget) (versions <= 4.3.2)
Is there a fix for CVE-2018-1000210? Yes. CVE-2018-1000210 is fixed in 5.0.0. Upgrade to this version or later.
Is CVE-2018-1000210 exploitable, and should I be worried? Whether CVE-2018-1000210 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
What actually determines whether CVE-2018-1000210 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
How do I fix CVE-2018-1000210?
- Upgrade YamlDotNet to 5.0.0 or later
- Upgrade YamlDotNet.Signed to 5.0.0 or later