Jenkins Debug Mode with Stack Traces Enabled Information Disclosure Scanner

Jenkins is a widely used open-source automation server that helps automate parts of software development related to building, testing, and deploying, facilitating continuous integration and delivery (CI/CD). It is used by software engineers and DevOps teams worldwide to streamline the development process and enhance productivity. Jenkins integrates with many other tools and services, making it an efficient solution for varied automation tasks. Debug mode in Jenkins is typically used by developers to troubleshoot problems during development or testing. However, running Jenkins in debug mode, especially in production systems, can lead to security risks. Its widespread use in critical environments means that any misconfiguration, like running in debug mode, could have significant implications.

Information disclosure vulnerabilities occur when sensitive data is divulged to unauthorized users. In many cases, this can happen due to systems running in debug or verbose modes, where excessive information is displayed in error messages or logs. These vulnerabilities may expose system paths, configuration details, and even stack traces, which could be leveraged by attackers for further exploitation. The vulnerability in Jenkins involves it being operated in debug mode, inadvertently enabling stack traces. Stack traces provide detailed error information that can include sensitive details about the application's internal processes, which should ideally remain hidden. Exploiting such vulnerabilities can lead to unauthorized access to sensitive information.

Technical details regarding the vulnerability involve the exposure of stack traces and specific error messages triggered by the application. These details are inadvertently enabled when Jenkins operates in debug mode. The endpoint involved could be any system page that experiences an error condition, returning detailed Java exception messages. The HTTP status code of 500 often accompanies these error messages, indicating improper handling of exceptional conditions within the application. The endpoint specified in the template checks for Java exception indicators in the response body, which are markers of stack traces and form the basis of this information disclosure vulnerability.

Exploiting the information disclosure vulnerability in Jenkins could lead attackers to extract sensitive information about system architecture, exposing potential weaknesses. Such details can facilitate more targeted attacks, potentially leading to unauthorized access or remote command execution. Attackers armed with this information could devise exploits custom-tailored to the environment, increasing the likelihood of success. When sensitive data is disclosed, it breaches confidentiality, as unauthorized parties obtain insights into the application's inner workings.

REFERENCES

• https://hackerone.com/reports/221833