CVE-2022-26884: Apache DolphinScheduler Log Server File Read Vulnerability and its Exploitation

Summary: The Apache DolphinScheduler log server, a popular open-source workflow management system, suffers from a file read vulnerability that allows attackers to read local files via specially crafted requests to the log server. This vulnerability has been assigned CVE-2022-26884 and affects versions of Apache DolphinScheduler before 2..6. Users should upgrade immediately to version 2..6 or higher to mitigate this vulnerability.

Introduction

Apache DolphinScheduler is a widely-used open-source workflow management platform designed for managing data pipelines and performing complex task scheduling. Recently, a file read vulnerability dubbed as CVE-2022-26884 has been discovered in its log server, which can allow unauthorized users to read local files with ease.

This article is intended for developers, administrators, and security enthusiasts who want to learn more about this vulnerability, understand how it can be exploited, and make sure their DolphinScheduler installations are safe from attacks based on this security issue.

The Vulnerability

The log server in Apache DolphinScheduler has a file read vulnerability that allows unauthorized users to read any files on the server. Essentially, this flaw is due to improper implementation of input validation mechanisms in the server, enabling attackers to use specially crafted requests to read files.

The affected versions of DolphinScheduler are those prior to version 2..6. It is highly recommended that users upgrade to version 2..6 or higher to prevent unauthorized file access resulting from this vulnerability.

Exploiting the Vulnerability

An attacker seeking to exploit this vulnerability could send a request to the log server with a specially crafted URL parameter. The server, upon receiving and processing the request, would return the contents of the requested file without any access restrictions.

Code Snippet to Illustrate the Exploit

http://<log-server>/download?fileName=../../../../../../etc/passwd

In this example, an attacker sends a GET request with the fileName parameter set to '../../../../../../etc/passwd', attempting to read the /etc/passwd file on the server. This file often contains sensitive data, such as user account details and hashed passwords. If the attacker is successful, he/she can use this information to compromise the system further.

Patches and Mitigation

As mentioned earlier, Apache DolphinScheduler has addressed this vulnerability by releasing version 2..6. Users should immediately upgrade their installations to this version or newer to prevent unauthorized file access through the log server. The latest release can be found here: https://dolphinscheduler.apache.org/en-us/docs/latest/user_doc/quick-start.html

Moreover, administrators should keep an eye out for security updates and best practices to maintain the security and privacy of their systems.

Conclusion and Additional Resources

CVE-2022-26884 is a critical security issue affecting the Apache DolphinScheduler log server. By allowing unauthorized users to read sensitive files on the server, it poses a significant risk to the confidentiality and integrity of the affected system. To protect against this vulnerability, users must upgrade to Apache DolphinScheduler 2..6 or higher.

For more information on CVE-2022-26884 and the related patch, please refer to the following resources:

- Official Apache DolphinScheduler Repository: https://github.com/apache/dolphinscheduler
- Apache DolphinScheduler Issue Tracker: https://github.com/apache/dolphinscheduler/issues/6728
- CVE-2022-26884 Mitre Reference: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2022-26884

Stay informed about security vulnerabilities in software you rely on by keeping your components up-to-date and regularly reviewing security bulletins and advisories.

Timeline

Published on: 10/28/2022 08:15:00 UTC
Last modified on: 10/31/2022 19:12:00 UTC