Malicious NuGet Packages Target ASP.NET Devs in Data Theft Campaign
Security researchers uncover four NuGet packages stealing ASP.NET Identity data, creating backdoors in web apps. Learn technical details and mitigation steps.
Malicious NuGet Packages Exfiltrate ASP.NET Identity Data
Cybersecurity researchers at Socket have identified four malicious NuGet packages designed to target ASP.NET web application developers. The packages steal sensitive ASP.NET Identity data—including user accounts, role assignments, and permission mappings—while also manipulating authorization rules to establish persistent backdoors in compromised applications.
Technical Details of the Attack
The malicious packages were discovered as part of a coordinated campaign exploiting NuGet, a popular package manager for .NET development. The attackers embedded malicious code within seemingly legitimate packages, allowing them to:
- Exfiltrate ASP.NET Identity data (user credentials, roles, permissions)
- Modify authorization rules to create hidden admin accounts
- Establish persistence by embedding backdoors in victim applications
While the original report did not disclose specific CVE IDs or package names, the attack vector aligns with recent trends in supply chain attacks targeting open-source ecosystems.
Impact on Developers and Organizations
The compromise of ASP.NET Identity data poses severe risks, including:
- Unauthorized access to sensitive user data
- Privilege escalation via manipulated role assignments
- Long-term persistence through backdoored applications
- Potential compliance violations under data protection regulations (e.g., GDPR, CCPA)
Developers using NuGet for ASP.NET projects should audit dependencies for suspicious packages and monitor for unusual authorization changes.
Mitigation and Next Steps
Security teams and developers are advised to:
- Scan NuGet dependencies using tools like Socket, OWASP Dependency-Check, or NuGet Package Explorer
- Review ASP.NET Identity configurations for unauthorized modifications
- Rotate credentials for all affected user accounts and roles
- Monitor for anomalous authentication attempts in application logs
- Implement supply chain security measures, such as package signing and provenance verification
Socket has reported the malicious packages to NuGet, which has likely taken action to remove them from the repository. However, developers should remain vigilant against similar threats in other package ecosystems, including npm, PyPI, and RubyGems.
For further details, refer to the original report by The Hacker News.