TanStack Unspecified Vulnerability
@tanstack — arktype-adapter
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.
9.6
2.3%
Vector breakdown
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- Required
- Scope
- Changed
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
- Published
- May 12, 2026
- Modified
- Jun 17, 2026
- Added to KEV
- May 27, 2026
- Federal patch due
- Jun 10, 2026
CISA required action
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Weakness classification
Affected packages
Proof-of-concept & exploitation references
8 foundWeaponization
Public repositories whose name or description references CVE-2026-45321, found via a live GitHub search at request time. These are community-sourced signals, not a verified working exploit - cross-check each one before relying on it, and treat higher star counts and recent activity as (weak) corroboration, not proof.
- fabriziosalmi/tanstack-compromise-checker★ 2
Shell script to detect TanStack npm supply chain attack indicators (CVE-2026-45321 / GHSA-g7cv-rxg3-hmpx)
updated Oct 5, 2026
- Intrudify/mini-shai-hulud-scanner★ 2
Scanner for the Mini Shai-Hulud npm/PyPI supply chain worm (NHS CC-4781 · CVE-2026-45321). Detects gh-token-monitor persistence, payload artefacts, and attacker commits. Python, Bash, PowerShell.
updated May 22, 2026
- nkopylov/tanscript-exploit-check★ 1
IOC checker for the TanStack/Mini Shai-Hulud npm supply chain attack (CVE-2026-45321)
updated May 26, 2026
- shayr1/shai-hulud-scan★ 1
Claude Code skill to scan machines for Mini Shai-Hulud (CVE-2026-45321) supply chain worm IOCs
updated May 18, 2026
- qi-scape/scan-shai-hulud★ 1
Detect CVE-2026-45321 Mini Shai-Hulud supply chain compromise — scans for 170 npm + 2 PyPI poisoned packages across TanStack, Mistral AI, UiPath, OpenSearch, Guardrails AI
updated May 22, 2026
- renewablehacking/CVE-2026-45321-Tanstack★ 0
updated May 25, 2026
- 7whyex/CVE-2026-45321-Tanstack★ 0
updated Jun 25, 2026
- Caixa-git/tanstack-shield★ 0
🛡️ One-command scanner for CVE-2026-45321 — TanStack npm supply-chain attack
updated May 12, 2026
References
Frequently asked questions
What is 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 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.
How severe is CVE-2026-45321?
CVE-2026-45321 has a CVSS base score of 9.6 out of 10 (CVSS 3.1).
Is CVE-2026-45321 actively exploited in the wild?
Yes. CVE-2026-45321 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, added May 27, 2026, meaning CISA has confirmed evidence of active exploitation. It is also flagged as used in ransomware campaigns.
What is the EPSS score for CVE-2026-45321?
2.3% - meaning FIRST.org's EPSS model estimates a 2.3% probability this vulnerability will be exploited in the wild within 30 days (82% percentile among all scored CVEs).
Is there exploit tooling available for CVE-2026-45321?
We found 8 public GitHub repositories referencing CVE-2026-45321, though none matched a known Nuclei template or Metasploit module at last check. Review each one before relying on it - see the proof-of-concept section above.
What type of vulnerability is CVE-2026-45321?
CVE-2026-45321 is classified under CWE-506 (CWE-506: Embedded Malicious Code).
Cross-checked against
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