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.
Is CVE-2026-45321 exploited?
Listed in the CISA KEV catalog on 2026-05-27.
Federal remediation due 2026-06-10.
Past that date by 66 days.
EPSS puts exploitation in the next 30 days at 2%.
Public exploit code: none found in monitored sources.