CVE-2026-45321

TanStack: Unspecified

As of , CVE-2026-45321 in TanStack is on CISA's list of exploited vulnerabilities: CISA listed it on . Our patch-first group: Patch now.

Exploited
Yes: CISA listed it on 27 May 2026
US federal deadline
10 June 202614 days after CISA listed it. US federal civilian agencies must fix it by then.
Used in ransomware campaigns
KnownCISA changed it from Unknown to Known on 28 May 2026.
EPSS score
0.01Higher than 63% of the CVEs EPSS scores. EPSS estimates the chance of exploitation activity in the next 30 days.
Public exploit
None foundNeither Metasploit nor Exploit-DB lists one.
Fix
Vendor advice: github.comLinks below, from CISA's entry.

What CISA says to do

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

CISA's required action

  • github.comThis vulnerability could affect an open-source component, third-party library, protocol, or proprietary implementation that could be used…

What the flaw is

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.

CISA's 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.

The CVE record's description, from GitHub_M

CVE published
12 May 2026
Assigned by
GitHub_M
CVSS
9.6 Critical (CVSS 3.1, from the CNA)
CWE-506
Embedded Malicious Code
CISA SSVC, exploitation
active
CISA SSVC, automatable
no
CISA SSVC, technical impact
total

Timeline

  1. The CVE record was published.
  2. CISA added it to its list of exploited vulnerabilities.
  3. CISA changed its entry. Ransomware use: Unknown to Known.
  4. The US federal deadline to fix it.

Read further