Detections
Analytics

Linux Distros Unpatched Vulnerability : CVE-2021-21303

medium Nessus Plugin ID 261355

Synopsis

The Linux/Unix host has one or more packages installed with a vulnerability that the vendor indicates will not be patched.

Description

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

 - 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. (CVE-2021-21303)

Note that Nessus relies on the presence of the package as reported by the vendor.

Solution

There is no known solution at this time.

See Also

https://ubuntu.com/security/CVE-2021-21303

Plugin Details

Severity: Medium

ID: 261355

File Name: unpatched_CVE_2021_21303.nasl

Version: 1.1

Type: local

Agent: unix

Family: Misc.

Published: 9/4/2025

Updated: 9/4/2025

Supported Sensors: Agentless Assessment, Frictionless Assessment Agent, Frictionless Assessment AWS, Frictionless Assessment Azure, Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.4

CVSS v2

Risk Factor: Low

Base Score: 3.5

Temporal Score: 2.6

Vector: CVSS2#AV:N/AC:M/Au:S/C:N/I:P/A:N

CVSS Score Source: CVE-2021-21303

CVSS v3

Risk Factor: Medium

Base Score: 6.8

Temporal Score: 5.9

Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:C/C:N/I:H/A:N

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:canonical:ubuntu_linux:25.04, cpe:/o:canonical:ubuntu_linux:20.04:-:lts, cpe:/o:canonical:ubuntu_linux:24.04:-:lts, cpe:/o:canonical:ubuntu_linux:16.04:-:lts, cpe:/o:canonical:ubuntu_linux:18.04:-:lts, cpe:/o:canonical:ubuntu_linux:22.04:-:lts, p-cpe:/a:canonical:ubuntu_linux:helm

Required KB Items: Host/cpu, Host/local_checks_enabled, global_settings/vendor_unpatched, Host/OS/identifier

Exploit Ease: No known exploits are available

Vulnerability Publication Date: 2/5/2021

Reference Information

CVE: CVE-2021-21303