CVE Vulnerabilities

CVE-2021-21303

Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')

Published: Feb 05, 2021 | Modified: Mar 13, 2023
CVSS 3.x
6.8
MEDIUM
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:N/I:H/A:N
CVSS 2.x
3.5 LOW
AV:N/AC:M/Au:S/C:N/I:P/A:N
RedHat/V2
RedHat/V3
Ubuntu

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.

Weakness

The product constructs all or part of a command, data structure, or record using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify how it is parsed or interpreted when it is sent to a downstream component.

Affected Software

Name Vendor Start Version End Version
Helm Helm 3.0.0 *

Potential Mitigations

References