On 2026-05-11, between approximately 19:20 and 19:26 UTC, 84 malicious versions across 42 @tanstack/* packages were published to the npm registry. The publishes were authenticated via the legitimate GitHub Actions OIDC trusted-publisher binding for TanStack/router, but the publish workflow itself was not modified. The attacker chained three known vulnerability classes — a pull_request_target "Pwn Request" misconfiguration, GitHub Actions cache poisoning across the fork↔base trust boundary, and runtime memory extraction of the OIDC token from the Actions runner process — to publish credential-stealing malware under a trusted identity. Each affected package received exactly two malicious versions, published a few minutes apart.
TanStack Query supplies asynchronous state management, server-state utilities and data fetching for the web. The `@tanstack/react-query-next-experimental` NPM package is vulnerable to a cross-site scripting vulnerability. To exploit this, an attacker would need to either inject malicious input or arrange to have malicious input be returned from an endpoint. To fix this issue, please update to version 5.18.0 or later.