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[ CVE-2026-45321 · Published 12 May 2026 ]

TanStack Unspecified Vulnerability

Exploited · CISA KEV CVSS 9.6 EPSS 1%No fix listed yet

[ Why it matters ]Priority signals

  • Exploited in the wild: on CISA's Known Exploited Vulnerabilities list since 2026-05-27
  • Known to be used in ransomware campaigns
  • Critical severity: CVSS 9.6

[ Description ]Official description

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.

CISA: TanStack contains an unspecified vulnerability that allowed malicious versions of the product to be published to the npm registry to publish credential-stealing malware under a trusted identity.

[ Fixes ]Fixes and patches

CISA required action (US federal deadline 10 Jun 2026): Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

No fix or interim patch is linked from our sources yet. Check the vendor references below and limit exposure of affected systems until a fix is available.

[ References ]References