CRITICAL · 9.6

CVE-2026-45321

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 G...

Vulnerability 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.

CVSS Score

9.6

CRITICAL

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
REQUIRED
Scope
CHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH

Affected Products

VendorProductVersions
TanstackTanstack\/Arktype-Adapter1.166.12
TanstackTanstack\/Eslint-Plugin-Router1.161.9
TanstackTanstack\/Eslint-Plugin-Start0.0.4
TanstackTanstack\/History1.161.9
TanstackTanstack\/Nitro-V2-Vite-Plugin1.154.12
TanstackTanstack\/React-Router1.169.5
TanstackTanstack\/React-Router-Devtools1.166.16
TanstackTanstack\/React-Router-Ssr-Query1.166.15
TanstackTanstack\/React-Start1.167.68
TanstackTanstack\/React-Start-Client1.166.51
TanstackTanstack\/React-Start-Rsc0.0.47
TanstackTanstack\/React-Start-Server1.166.55
TanstackTanstack\/Router-Cli1.166.46
TanstackTanstack\/Router-Core1.169.5
TanstackTanstack\/Router-Devtools1.166.16
TanstackTanstack\/Router-Devtools-Core1.167.6
TanstackTanstack\/Router-Generator1.166.45
TanstackTanstack\/Router-Plugin1.167.38
TanstackTanstack\/Router-Ssr-Query-Core1.168.3
TanstackTanstack\/Router-Utils1.161.11

Related Weaknesses (CWE)

References

FAQ

What is CVE-2026-45321?

CVE-2026-45321 is a vulnerability with a CVSS score of 9.6 (CRITICAL). 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 G...

How severe is CVE-2026-45321?

CVE-2026-45321 has been rated CRITICAL with a CVSS base score of 9.6/10. This is considered a critical vulnerability requiring immediate attention.

Is there a patch for CVE-2026-45321?

Check the references section above for vendor advisories and patch information. Affected products include: Tanstack Tanstack\/Arktype-Adapter, Tanstack Tanstack\/Eslint-Plugin-Router, Tanstack Tanstack\/Eslint-Plugin-Start, Tanstack Tanstack\/History, Tanstack Tanstack\/Nitro-V2-Vite-Plugin.