CVE-2021-41254
CVSS V2 High 9
CVSS V3 High 8.8
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.
Overview
- CVE ID
- CVE-2021-41254
- Assigner
- security-advisories@github.com
- Vulnerability Status
- Analyzed
- Published Version
- 2021-11-12T18:15:07
- Last Modified Date
- 2021-11-17T13:29:20
Weakness Enumerations
CPE Configuration (Product)
| CPE | Vulnerable | Operator | Version Start | Version End |
|---|---|---|---|---|
| cpe:2.3:a:fluxcd:kustomize-controller:*:*:*:*:*:*:*:* | 1 | OR | 0.15.0 |
CVSS Version 2
- Version
- 2.0
- Vector String
- AV:N/AC:L/Au:S/C:C/I:C/A:C
- Access Vector
- NETWORK
- Access Compatibility
- LOW
- Authentication
- SINGLE
- Confidentiality Impact
- COMPLETE
- Integrity Impact
- COMPLETE
- Availability Impact
- COMPLETE
- Base Score
- 9
- Severity
- HIGH
- Exploitability Score
- 8
- Impact Score
- 10
CVSS Version 3
- Version
- 3.1
- Vector String
- CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- Attack Vector
- NETWORK
- Attack Compatibility
- LOW
- Privileges Required
- LOW
- User Interaction
- NONE
- Scope
- UNCHANGED
- Confidentiality Impact
- HIGH
- Availability Impact
- HIGH
- Base Score
- 8.8
- Base Severity
- HIGH
- Exploitability Score
- 2.8
- Impact Score
- 5.9
References
| Reference URL | Reference Tags |
|---|---|
| https://github.com/fluxcd/kustomize-controller/security/advisories/GHSA-35rf-v2jv-gfg7 | Exploit Mitigation Third Party Advisory |
Sources
| Source Name | Source URL |
|---|---|
| NIST | https://nvd.nist.gov/vuln/detail/CVE-2021-41254 |
| MITRE | https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-41254 |
History
| Created | Old Value | New Value | Data Type | Notes |
|---|---|---|---|---|
| 2022-05-10 06:46:36 | Added to TrackCVE | |||
| 2022-12-05 14:25:48 | 2021-11-12T18:15Z | 2021-11-12T18:15:07 | CVE Published Date | updated |
| 2022-12-05 14:25:48 | 2021-11-17T13:29:20 | CVE Modified Date | updated | |
| 2022-12-05 14:25:48 | Analyzed | Vulnerability Status | updated |