8.8
HIGH
CVE-2021-41254
Kustomize-Controller Unauthenticated Command Execution Vulnerability
Description

kustomize-controller is a Kubernetes operator, specialized in running continuous delivery pipelines for infrastructure and workloads defined with Kubernetes manifests and assembled with Kustomize. Users that can create Kubernetes Secrets, Service Accounts and Flux Kustomization objects, could execute commands inside the kustomize-controller container by embedding a shell script in a Kubernetes Secret. This can be used to run `kubectl` commands under the Service Account of kustomize-controller, thus allowing an authenticated Kubernetes user to gain cluster admin privileges. In affected versions multitenant environments where non-admin users have permissions to create Flux Kustomization objects are affected by this issue. This vulnerability was fixed in kustomize-controller v0.15.0 (included in flux2 v0.18.0) released on 2021-10-08. Starting with v0.15, the kustomize-controller no longer executes shell commands on the container OS and the `kubectl` binary has been removed from the container image. To prevent the creation of Kubernetes Service Accounts with `secrets` in namespaces owned by tenants, a Kubernetes validation webhook such as Gatekeeper OPA or Kyverno can be used.

INFO

Published Date :

Nov. 12, 2021, 6:15 p.m.

Last Modified :

Nov. 17, 2021, 1:29 p.m.

Remotely Exploitable :

Yes !

Impact Score :

5.9

Exploitability Score :

2.8
Affected Products

The following products are affected by CVE-2021-41254 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Fluxcd kustomize-controller
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2021-41254.

URL Resource
https://github.com/fluxcd/kustomize-controller/security/advisories/GHSA-35rf-v2jv-gfg7 Exploit Mitigation Third Party Advisory

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2021-41254 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2021-41254 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by [email protected]

    May. 14, 2024

    Action Type Old Value New Value
  • Initial Analysis by [email protected]

    Nov. 17, 2021

    Action Type Old Value New Value
    Added CVSS V2 NIST (AV:N/AC:L/Au:S/C:C/I:C/A:C)
    Added CVSS V3.1 NIST AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
    Changed Reference Type https://github.com/fluxcd/kustomize-controller/security/advisories/GHSA-35rf-v2jv-gfg7 No Types Assigned https://github.com/fluxcd/kustomize-controller/security/advisories/GHSA-35rf-v2jv-gfg7 Exploit, Mitigation, Third Party Advisory
    Added CWE NIST CWE-78
    Added CPE Configuration OR *cpe:2.3:a:fluxcd:kustomize-controller:*:*:*:*:*:*:*:* versions up to (excluding) 0.15.0
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2021-41254 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Exploit Prediction

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.

0.31 }} 0.09%

score

0.69824

percentile

CVSS31 - Vulnerability Scoring System
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