Over 244,000 downloads
A sophisticated supply chain attack has targeted the AI/ML developer community through the popular Hugging Face platform. Threat actors created a malicious repository that impersonated a legitimate project from OpenAI, tricking users into downloading infostealing malware. The fake repository, which typosquatted OpenAI's "Privacy Filter" project, leveraged social engineering and likely bots to reach the #1 trending spot on Hugging Face, lending it an air of legitimacy. Before being taken down, the malware was downloaded over 244,000 times. The payload was an infostealer designed to harvest a wide range of sensitive data from victims' machines. This incident highlights the vulnerability of open-source ecosystems and the increasing trend of attackers targeting the AI development pipeline.
The attack centered on a malicious Hugging Face repository named Open-OSS/privacy-filter. The attackers employed several deceptive tactics:
The malware payload was an infostealer targeting Windows systems. It was equipped with anti-analysis capabilities, including checks for virtual machines, sandboxes, and debuggers, to evade detection. Upon execution, the malware would steal a wide array of sensitive data, including:
The stolen data was compressed and exfiltrated to a command-and-control (C2) server located at recargapopular[.]com.
This campaign is a classic example of a supply chain attack targeting developers by poisoning an open-source repository.
MITRE ATT&CK Techniques:
T1195.001 - Compromise Software Supply Chain: Compromise Software Distribution: The attackers published malicious code to a trusted public repository (Hugging Face) to distribute malware.T1555 - Credentials from Password Stores: The infostealer was designed to steal credentials from browsers and other applications.T1539 - Steal Web Session Cookie: The malware targeted browser session tokens to hijack active user sessions.T1631 - Steal Application Access Token: Specifically targeting crypto wallets involves stealing access tokens or private keys.T1497 - Virtualization/Sandbox Evasion: The malware included checks for VMs and debuggers to avoid analysis.T1071.001 - Application Layer Protocol: Web Protocols: The stolen data was exfiltrated over HTTP/HTTPS to the C2 server.Developers and organizations that downloaded and used code from this malicious repository are at high risk.
recargapopular[.]comOpen-OSS/privacy-filterrecargapopular[.]com.Open-OSS/privacy-filter repository on Hugging Face.VMWare, VirtualBox, or debugger processes before executing their main payload.recargapopular[.]com at the network perimeter. Scan network logs for any historical connections.D3-PA - Process Analysis): EDR tools can be configured to detect common infostealer behaviors, such as a process accessing credential stores of multiple web browsers, querying for cryptocurrency wallet files, and then making an external network connection.D3-UT - User Training): Train developers on the risks of supply chain attacks and how to spot suspicious open-source projects. This includes verifying publishers, checking for typosquatting, and being skeptical of projects with suspiciously high, inorganic-looking popularity metrics.Executing untrusted code from open-source repositories in a sandboxed environment can prevent it from accessing sensitive data on the host machine.
Mapped D3FEND Techniques:
Training developers to be skeptical of open-source packages, check for signs of typosquatting, and verify publisher reputation is a critical defense.
Blocking known malicious C2 domains at the network egress point can prevent data exfiltration even if a system is compromised.
Mapped D3FEND Techniques:
To combat supply chain attacks like the one on Hugging Face, organizations must treat all new open-source components as potentially malicious. A key defense is to subject these components to Dynamic Analysis in a secure, isolated sandbox before they are introduced into the development lifecycle. For the fake 'privacy-filter' package, a sandbox would execute the code and monitor its behavior. It would observe the malware's anti-VM checks, its attempts to access browser credential stores (e.g., Local State and Login Data files in Chrome), its search for crypto wallet files, and critically, its attempt to exfiltrate data to the C2 server at recargapopular[.]com. This provides a definitive verdict on the malicious nature of the package without ever exposing a real developer machine to risk. This process should be automated as part of a secure software development lifecycle (SSDLC).
Outbound Traffic Filtering is a crucial reactive defense that can prevent data loss even after a developer's machine is compromised by an infostealer. Security teams should implement egress filtering rules on perimeter firewalls and web proxies that deny all outbound connections by default, only allowing traffic to known-good, categorized domains required for business operations. When the infostealer from the fake Hugging Face repo attempted to send stolen data to recargapopular[.]com, this connection would be blocked because the domain is unknown and uncategorized. The blocked connection attempt should then generate a high-priority alert for the security operations center (SOC) to investigate. This not only prevents the immediate data loss but also serves as a high-fidelity indicator that a host on the internal network is compromised.
The malicious repository was removed from the Hugging Face platform.

Cybersecurity professional with over 10 years of specialized experience in security operations, threat intelligence, incident response, and security automation. Expertise spans SOAR/XSOAR orchestration, threat intelligence platforms, SIEM/UEBA analytics, and building cyber fusion centers. Background includes technical enablement, solution architecture for enterprise and government clients, and implementing security automation workflows across IR, TIP, and SOC use cases.
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Every tactic, technique, and sub-technique used in this threat has been identified and mapped to the MITRE ATT&CK framework for consistent, actionable threat language.
Observables and indicators of compromise (IOCs) have been extracted and cataloged. Risk has been assessed and correlated with known threat actors and historical campaigns.
Detection rules, incident response steps, and D3FEND-aligned mitigation strategies are included so your team can act on this intelligence immediately.
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