Skip to content

Commit

Permalink
Create rule S6868: Allowing command execution is security sensitive (#…
Browse files Browse the repository at this point in the history
…3513)

* Create rule S6868

* Added description for S6868

* Removed title duplicate

* Adjusted code example language

* Update rules/S6868/kubernetes/rule.adoc

Co-authored-by: Sebastien Andrivet <138577785+sebastien-andrivet-sonarsource@users.noreply.github.com>

---------

Co-authored-by: daniel-teuchert-sonarsource <daniel-teuchert-sonarsource@users.noreply.github.com>
Co-authored-by: Daniel Teuchert <daniel.teuchert@sonarsource.com>
Co-authored-by: daniel-teuchert-sonarsource <141642369+daniel-teuchert-sonarsource@users.noreply.github.com>
Co-authored-by: Sebastien Andrivet <138577785+sebastien-andrivet-sonarsource@users.noreply.github.com>
  • Loading branch information
5 people authored Dec 19, 2023
1 parent dcac610 commit b5a13fe
Show file tree
Hide file tree
Showing 3 changed files with 127 additions and 0 deletions.
29 changes: 29 additions & 0 deletions rules/S6868/kubernetes/metadata.json
Original file line number Diff line number Diff line change
@@ -0,0 +1,29 @@
{
"title": "Allowing command execution is security sensitive",
"type": "VULNERABILITY",
"status": "ready",
"remediation": {
"func": "Constant\/Issue",
"constantCost": "5min"
},
"tags": [
],
"defaultSeverity": "Major",
"ruleSpecification": "RSPEC-6868",
"sqKey": "S6868",
"scope": "All",
"securityStandards": {
"CWE": [
284
]
},
"defaultQualityProfiles": ["Sonar way"],
"quickfix": "unknown",
"code": {
"impacts": {
"MAINTAINABILITY": "LOW",
"SECURITY": "LOW"
},
"attribute": "COMPLETE"
}
}
96 changes: 96 additions & 0 deletions rules/S6868/kubernetes/rule.adoc
Original file line number Diff line number Diff line change
@@ -0,0 +1,96 @@
== Why is this an issue?

Allowing command execution (exec) for roles in a Kubernetes cluster can pose a significant security risk. This is because it provides the user with the ability to execute arbitrary commands within a container, potentially leading to unauthorized access or data breaches.

In a production Kubernetes cluster, exec permissions are typically unnecessary due to the principle of least privilege, which suggests that a user or process should only have the minimum permissions necessary to perform its function. Additionally, containers in production are often treated as immutable infrastructure, meaning they should not be changed once deployed. Any changes should be made to the container image, which is then used to deploy a new container.

=== What is the potential impact?

==== Exploiting Vulnerabilities Within the Container

If a user or service has the ability to execute commands within a container, they could potentially identify and exploit vulnerabilities within the container's software. This could include exploiting known vulnerabilities in outdated software versions, or finding and exploiting new vulnerabilities. This could lead to unauthorized access to the container, allowing the attacker to manipulate its operations or access its data.

==== Installing Malicious Software

Command execution permissions could also be used to install malicious software within a container. This could include malware, spyware, ransomware, or other types of harmful software. Once installed, this software could cause a wide range of issues, from data corruption or loss, to providing a backdoor for further attacks. It could also be used to create a botnet, using the compromised container to launch attacks on other systems.

==== Extracting Sensitive Data

If an attacker has the ability to execute commands within a container, they could potentially access and extract sensitive data. This could include user data, confidential business information, or other types of sensitive data. The extracted data could then be used for a wide range of malicious purposes, from identity theft to corporate espionage. This could lead to significant financial loss, damage to reputation, and potential legal consequences.

== How to fix it

=== Code examples

==== Noncompliant code example

[source,yaml,diff-id=1,diff-type=noncompliant]
----
apiVersion: rbac.authorization.k8s.io/v1
kind: Role
metadata:
namespace: default
name: example-role
rules:
- apiGroups: [""]
resources: ["pods"]
verbs: ["get"]
- apiGroups: [""]
resources: ["pods/exec"] # Noncompliant
verbs: ["create"]
----

==== Compliant solution

[source,yaml,diff-id=1,diff-type=compliant]
----
apiVersion: rbac.authorization.k8s.io/v1
kind: Role
metadata:
namespace: default
name: example-role
rules:
- apiGroups: [""]
resources: ["pods"]
verbs: ["get"]
----

=== How does this work?

The `exec` permissions are set by allowing the `create` verb for the `pods/exec` resource. Removing this permission will prevent users and services from executing arbitrary commands within containers.

//=== Pitfalls

//=== Going the extra mile


== Resources
=== Documentation

* Kubernetes Documentation - https://kubernetes.io/docs/tasks/debug/debug-application/get-shell-running-container/[Get a Shell to a Running Container]

//=== Articles & blog posts
//=== Conference presentations
=== Standards
* CWE - https://cwe.mitre.org/data/definitions/284[CWE-284 - Improper Access Control]

//=== External coding guidelines
//=== Benchmarks

ifdef::env-github,rspecator-view[]

'''
== Implementation Specification
(visible only on this page)

=== Message

Remove the command execution permission for this role.


=== Highlighting

* Highlight the `resources` property.


endif::env-github,rspecator-view[]
2 changes: 2 additions & 0 deletions rules/S6868/metadata.json
Original file line number Diff line number Diff line change
@@ -0,0 +1,2 @@
{
}

0 comments on commit b5a13fe

Please sign in to comment.