A severe security vulnerability (CVE-2022-44054) has been discovered in the d8s-xml Python package, as distributed on the Python Package Index (PyPI). The package contains a potential code-execution backdoor inserted by a third party, posing a serious risk to unsuspecting users. The affected version of d8s-xml is .1., and it is crucial for users to refrain from using this version of the package until a patch is released.

This vulnerability brings attention to the importance of carefully evaluating and vetting dependencies in any software project, as third-party packages can introduce unintended security risks.

Details

The d8s-xml package is a Python library that provides XML parsing and manipulation utilities. The vulnerability stems from the inclusion of the 'democritus-utility' package, which was found to contain the code-execution backdoor. Attackers could potentially leverage this security flaw to execute arbitrary code on the systems of developers and end-users who have this package installed.

A code snippet example demonstrating the presence of the backdoor in the 'democritus-utility' package is provided below:

# democritus-utility package - vulnerable function
def potentially_malicious_function(user_input):
    data = None
    try:
        data = eval(user_input)
    except:
        pass
    return data

This function takes the user's input (a string) and 'eval()' function is used to execute the code within the input, potentially allowing attackers to execute arbitrary code if they manage to pass a malicious payload to the function.

Exploit

A hypothetical exploit scenario involves a malicious actor deceiving users into passing a payload (disguised as a harmless string) into an application that depends on the d8s-xml package:

1. Attacker crafts a malicious payload string, e.g., "().__class__.__bases__[].__subclasses__()[135]('rm -rf /', shell=True)"
2. Attacker tricks the user into inputting the payload into an application built on the d8s-xml package.
3. The payload triggers the vulnerable 'potentially_malicious_function()' from the democritus-utility package, and the code within the payload string is executed.

Mitigation

Users of the d8s-xml package should immediately stop using version .1. and inform the maintainers of this package about the issue if they haven't been made aware already. It is recommended to update to a patched version as soon as it becomes available or look for alternative libraries.

Maintainers of similar projects with external dependencies should conduct a thorough audit to ensure the use of safe and trusted libraries. Regular security audits and vulnerability scanning can help detect and prevent the spread of such security risks in the software supply chain.

CVE-2022-44054

For a comprehensive list of common vulnerabilities and exposures, visit the following site

Common Vulnerabilities and Exposures

Further details on safe dependency management practices and known vulnerable packages can be found in the following resources:
- OWASP Safe Dependency Management
- Python Safety DB
- Python Security Advisories

Conclusion

This vulnerability (CVE-2022-44054) demonstrates the need for vigilance and due diligence in the world of open-source software development. It is important to take steps to avoid potential security risks by conducting regular security audits of codebases and dependencies, and staying informed about known vulnerabilities.

Timeline

Published on: 11/07/2022 15:15:00 UTC
Last modified on: 11/08/2022 16:23:00 UTC