Security researchers have identified a new npm supply chain attack making its way through developer environments, stealing credentials and sensitive data as it propagates through compromised packages. The campaign, reported by The Register on April 22, 2026, represents the latest in a series of attacks targeting the JavaScript ecosystem's package registry.
The malicious payload contains references to a 'TeamPCP/LiteLLM method,' and investigators note significant technical overlap with open source package infections previously attributed to the TeamPCP group. This connection suggests either the same threat actor is behind both campaigns or that attackers are reusing and adapting existing malicious tooling.
How the Attack Works
Supply chain attacks on npm typically involve threat actors publishing malicious packages with names designed to mimic popular, legitimate libraries — a technique known as typosquatting — or, in more sophisticated cases, compromising maintainer accounts to inject malicious code directly into widely-trusted packages. Once a developer installs an infected package, the malware can execute in their environment, scanning for API keys, environment variables, authentication tokens, and other sensitive credentials.
The worm-like propagation mechanism noted in this campaign suggests the malware may be capable of spreading laterally once embedded in a development environment, potentially beyond the initial point of compromise.
A Recurring Problem
The npm registry, which hosts over two million packages and serves as a foundational tool for the global JavaScript developer community, has long been a target for supply chain attackers. The sheer volume of packages, combined with the trust developers place in the ecosystem, creates persistent attack opportunities that security teams struggle to fully close.
The LiteLLM reference in the payload is notable — LiteLLM is a popular open source library used to interface with large language model APIs, suggesting attackers may be targeting developers working in AI-adjacent tooling, a rapidly growing segment of the developer community.
Developer Precautions
Security professionals generally recommend developers audit their dependency trees regularly, use tools like npm audit or third-party software composition analysis (SCA) platforms, pin dependency versions where possible, and treat environment variables and secrets as potentially exposed when an unexpected package has been installed. Organisations using private package registries or allowlists may have greater protection against such attacks.
At the time of publication, full details on which specific packages are affected had not been disclosed, and it remains unclear how many developer environments have been compromised.