CVE-2021-39132 : Vulnerability Insights and Analysis

Rundeck prior to versions 3.3.14 and 3.4.3 allows an authorized user to execute untrusted code through crafted files. Learn more about this CVE and its impact.

Understanding CVE-2021-39132

Rundeck is an open-source automation service with various vulnerabilities related to YAML deserialization, allowing the execution of untrusted code.

What is CVE-2021-39132?

Rundeck versions prior to 3.3.14 and 3.4.3 enable authorized users to upload files that contain crafted data, leading to the execution of untrusted code on Rundeck Community or Enterprise Edition.

The Impact of CVE-2021-39132

The CVSS score for this vulnerability is 8.8, indicating a high severity level due to its potential for confidentiality, integrity, and availability impact. The attack complexity is low, but it can be exploited over a network without user interaction.

Technical Details of CVE-2021-39132

Explore the vulnerability description, affected systems, and exploitation mechanism below.

Vulnerability Description

The vulnerability arises from the deserialization of untrusted data in YAML files, allowing malicious users to run arbitrary code on Rundeck servers.

Affected Systems and Versions

Product: Rundeck
Vendor: Rundeck
Affected Versions:
< 3.3.14

= 3.4.0, < 3.4.3

Exploitation Mechanism

An authorized user can exploit this vulnerability by uploading a zip-format plugin with a crafted plugin.yaml or aclpolicy yaml file or an untrusted project archive with a crafted aclpolicy yaml file. Additionally, an authenticated user can trigger the execution of untrusted code through a POST request.

Mitigation and Prevention

Discover essential steps to mitigate the risks and safeguard your systems against CVE-2021-39132.

Immediate Steps to Take

Update Rundeck to versions 3.4.3 or 3.3.14, which contain patches addressing this vulnerability.
Review and restrict user permissions to prevent unauthorized file uploads.

Long-Term Security Practices

Educate users on safe file upload practices and the risks associated with untrusted files.
Implement regular security training sessions to enhance awareness of potential vulnerabilities and best practices.

Patching and Updates

Regularly monitor and apply security patches provided by Rundeck to prevent exploitation of known vulnerabilities.