TeamPCP Compromises 170+ npm, PyPI Packages

A coordinated supply chain attack compromised more than 170 software packages across npm and PyPI on May 11, 2026, security analysis revealed. The threat group known as TeamPCP exploited weaknesses in GitHub Actions workflows to hijack legitimate release pipelines, publishing hundreds of malicious package versions laced with the Mini ShaiHulud worm.

The assault struck high-profile projects including 42 TanStack packages such as the widely used TanStack Router library, which receives millions of weekly downloads; 65 UiPath packages; more than 20 Squawk packages; Mistral AI's SDK on both npm and PyPI; the Guardrails AI PyPI package; and the OpenSearch JavaScript client. Estimates of affected packages ranged from 169 to 172 unique namespaces, with 373 to 404 malicious versions published in a narrow window of several hours. Automated security tools from multiple vendors detected the activity almost immediately.

Attackers gained access without stealing maintainer credentials directly. They targeted misconfigured pull_request_target triggers in GitHub Actions, which allow third-party workflows to run without approval. By forking repositories and opening malicious pull requests, the...