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Kubernetes CVE-2021-21303

MEDIUM
Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection') (CWE-74)
2021-02-05 security-advisories@github.com
6.8
CVSS 3.1 · NVD
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Severity by source

NVD PRIMARY
6.8 MEDIUM
AV:N/AC:L/PR:L/UI:R/S:C/C:N/I:H/A:N

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:N/I:H/A:N
Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
Required
Scope
Changed
Confidentiality
None
Integrity
High
Availability
None

Lifecycle Timeline

1
CVE Published
Feb 05, 2021 - 22:15 nvd
MEDIUM 6.8

DescriptionNVD

Helm is open-source software which is essentially "The Kubernetes Package Manager". Helm is a tool for managing Charts. Charts are packages of pre-configured Kubernetes resources. In Helm from version 3.0 and before version 3.5.2, there a few cases where data loaded from potentially untrusted sources was not properly sanitized. When a SemVer in the version field of a chart is invalid, in some cases Helm allows the string to be used "as is" without sanitizing. Helm fails to properly sanitized some fields present on Helm repository index.yaml files. Helm does not properly sanitized some fields in the plugin.yaml file for plugins In some cases, Helm does not properly sanitize the fields in the Chart.yaml file. By exploiting these attack vectors, core maintainers were able to send deceptive information to a terminal screen running the helm command, as well as obscure or alter information on the screen. In some cases, we could send codes that terminals used to execute higher-order logic, like clearing a terminal screen. Further, during evaluation, the Helm maintainers discovered a few other fields that were not properly sanitized when read out of repository index files. This fix remedies all such cases, and once again enforces SemVer2 policies on version fields. All users of the Helm 3 should upgrade to the fixed version 3.5.2 or later. Those who use Helm as a library should verify that they either sanitize this data on their own, or use the proper Helm API calls to sanitize the data.

AnalysisAI

Helm is open-source software which is essentially "The Kubernetes Package Manager". Rated medium severity (CVSS 6.8), this vulnerability is remotely exploitable, low attack complexity.

Technical ContextAI

This vulnerability is classified under CWE-74. Helm is open-source software which is essentially "The Kubernetes Package Manager". Helm is a tool for managing Charts. Charts are packages of pre-configured Kubernetes resources. In Helm from version 3.0 and before version 3.5.2, there a few cases where data loaded from potentially untrusted sources was not properly sanitized. When a SemVer in the version field of a chart is invalid, in some cases Helm allows the string to be used "as is" without sanitizing. Helm fails to properly sanitized some fields present on Helm repository index.yaml files. Helm does not properly sanitized some fields in the plugin.yaml file for plugins In some cases, Helm does not properly sanitize the fields in the Chart.yaml file. By exploiting these attack vectors, core maintainers were able to send deceptive information to a terminal screen running the helm command, as well as obscure or alter information on the screen. In some cases, we could send codes that terminals used to execute higher-order logic, like clearing a terminal screen. Further, during evaluation, the Helm maintainers discovered a few other fields that were not properly sanitized when read out of repository index files. This fix remedies all such cases, and once again enforces SemVer2 policies on version fields. All users of the Helm 3 should upgrade to the fixed version 3.5.2 or later. Those who use Helm as a library should verify that they either sanitize this data on their own, or use the proper Helm API calls to sanitize the data. Affected products include: Helm. Version information: version 3.0.

RemediationAI

A vendor patch is available. Apply the latest security update as soon as possible. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.

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CVE-2021-21303 vulnerability details – vuln.today

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