CVE-2023-48311 Explained : Impact and Mitigation

A vulnerability has been identified in the dockerspawner component used to spawn JupyterHub single user servers in Docker containers. This article provides detailed insights into CVE-2023-48311, including its impact, technical details, and mitigation measures.

Understanding CVE-2023-48311

This section delves into the specifics of the vulnerability and its implications for systems running dockerspawner.

What is CVE-2023-48311?

The dockerspawner tool allows the spawning of JupyterHub single user servers in Docker containers. Users of JupyterHub deployments running DockerSpawner version 0.11.0 and above may unknowingly grant permissions to run any Docker image, instead of the intended restricted image, due to a configuration oversight.

The Impact of CVE-2023-48311

The vulnerability enables unauthorized users to launch arbitrary Docker images, bypassing intended restrictions. This could lead to the execution of malicious code, data breaches, and unauthorized access to sensitive information.

Technical Details of CVE-2023-48311

This section outlines the specifics of CVE-2023-48311, including the vulnerability description, affected systems, and the exploitation mechanism.

Vulnerability Description

Users of dockerspawner versions 0.11.0 to 12.0 are affected by this vulnerability. The issue arises from the failure to specify the

DockerSpawner.allowed_images

configuration, allowing the launch of any Docker image instead of the intended single configured image.

Affected Systems and Versions

The vulnerability impacts JupyterHub deployments using dockerspawner versions from 0.11.0 to 12.0. Systems within this range are susceptible to the improper input validation vulnerability.

Exploitation Mechanism

Unauthorized users can exploit the misconfiguration in DockerSpawner to launch arbitrary Docker images, potentially compromising system integrity and confidentiality.

Mitigation and Prevention

This section provides guidance on immediate steps to take and long-term security practices to prevent exploitation and mitigate the effects of CVE-2023-48311.

Immediate Steps to Take

Affected users are advised to upgrade dockerspawner to version 13.0 or above, where the vulnerability has been addressed. Alternatively, users can explicitly set

DockerSpawner.allowed_images

to a non-empty list with only the default image to enforce the intended behavior.

Long-Term Security Practices

To enhance system security, users should regularly update dockerspawner to the latest version, configure proper image restrictions, and conduct security audits to identify and mitigate similar vulnerabilities.

Patching and Updates

Stay informed about security patches and updates released by the vendor. Timely implementation of patches can safeguard systems against known vulnerabilities and threats.