IceKube

IceKube is a tool to help find attack paths within a Kubernetes cluster from a low privileged point, to a preferred location, typically cluster-admin

Setup

• docker-compose up -d - Spins up neo4j, accessible at http://localhost:7474/

• poetry install --no-dev (creates venv) OR pip install --user . (installs the CLI globally)

• Make sure your kubectl current context is set to the target cluster, and has cluster-admin privileges

• IceKube is also available directly through pip with - pip install icekube

• Neo4j can be spun up directly with docker with - docker run -d -p 7474:7474 -p 7687:7687 -e NEO4J_AUTH=none -v $PWD/data:/data neo4j:4.4

Permissions Required

This requires elevated privileges within the target cluster to enumerate resources. This typically requires read-only access on all resources within the cluster including secrets. IceKube does not persist any secret data it retrieves from secrets if that is a concern.

Resource types can also be filtered from IceKube, instructions can be found below in the Filtering Resources section.

Usage

• icekube enumerate - Will enumerate all resources, and saves them into neo4j with generic relationships generated (note: not attack path relationships)
• icekube attack-path - Generates attack path relationships within neo4j, these are identified with relationships having the property attack_path which is set to 1
• icekube run - Does both enumerate and attack-path, this will be the main option for quickly running IceKube against a cluster
• icekube purge - Removes everything from the neo4j database
• Run cypher queries within neo4j to discover attack paths and roam around the data, attack relationships will have the property attack_path: 1

NOTE: In the neo4j browser, make sure to disable Connect result nodes in the Settings tab on the bottom left. This will stop it rendering every possible relationship automatically between nodes, leaving just the path queried for

The contents of the cluster can also be downloade with icekube download or through freezer (a rust implementation of icekube download) and then loaded in through icekube load.

Filtering Resources

It is possible to filter out specific resource types from enumeration. This can be done with the --ignore parameter to enumerate and run which takes the resource types comma-delimtied. For example, if you wish to exclude events and componentstatuses, you could run icekube run --ignore events,componentstatuses (NOTE: this is the default)

Sensitive data from secrets are not stored in IceKube, data retrieved from the Secret resource type have their data fields deleted on ingestion. It is recommended to include secrets as part of the query if possible as IceKube can still analyse the secret type and relevant annotations to aid with attack path generation.

Not sure where to start?

Here is a quick introductory way on running IceKube for those new to the project:

• poetry install - Installs dependancies using poetry
• poetry shell - Create a shell within the python environment
• docker-compose up -d - Creates the neo4j docker container with easy to use network and environment settings (give this a minute for neo4j to start up)
• icekube run - Analyse a cluster using IceKube - this assumes your kubectl context is set appropriately to target a cluster
• Open the neo4j browser at http://localhost:7474/
• On the login form, simply click Connect - wait for the connection to be established
• Click the cog wheel on the bottom left to open settings
• Near the bottom of the new side-pane, de-select Connect result nodes
• Enter the following query into the query bar at the top
  • MATCH p = SHORTEST 1 (src)-[r {attack_path: 1}]->+(crb:ClusterRoleBinding)-[:GRANTS_PERMISSION {attack_path: 1}]->(cr:ClusterRole {name: "cluster-admin"}) RETURN p
  • This will find routes to cluster administrator from service accounts, pods, users, or groups
• Of the new window made with the query, click the Fullscreen button
• Roam around the graph generated, clicking on nodes or relationships to get more details on the right where wanted

Example Cypher Queries

The following query will find all resources that have cluster-admin permissions. This is enforced through a Cluster Role Binding to ensure the permissions are cluster-wide

MATCH p = SHORTEST 1 (src)-[r {attack_path: 1}]->+(crb:ClusterRoleBinding)-[:GRANTS_PERMISSION {attack_path: 1}]->(cr:ClusterRole {name: "cluster-admin"}) RETURN p

This performs the same, but restricts the query to start at nodes of type Pod / ServiceAccount / User / Group

MATCH p = SHORTEST 1 (src)-[r {attack_path: 1}]->+(crb:ClusterRoleBinding)-[:GRANTS_PERMISSION {attack_path: 1}]->(cr:ClusterRole {name: "cluster-admin"}) WHERE (src:ServiceAccount OR src:Pod or src:User or src:Group) RETURN p

Using the old shortestPath syntax:

MATCH (crb:ClusterRoleBinding)-[r:GRANTS_PERMISSION {attack_path: 1}]->(cr:ClusterRole {name: 'cluster-admin'})
WITH crb, cr, r
MATCH (src) WHERE src:ServiceAccount OR src:Pod OR src:User or src:Group
WITH src, crb, cr, r
UNWIND src as s
MATCH p=shortestPath((s)-[*]->(crb))
WHERE all(r in relationships(p) where r.attack_path is not null)
RETURN p, cr, r

Acknowledgements

• BloodHound - The original project showing the power of graph databases for security
• KubeHound - An excellent and similar tool by DataDog, clearly we had similar ideas!