CriticalCVE-2026-45321

    Malware in 42 @tanstack/* packages exfiltrates cloud credentials, GitHub tokens, and SSH keys (CVE-2026-45321)

    Published Last modified In CISA KEV since Sources: CVE.org, pwn.watch, EUVD, OSV

    What is affected, what to do

    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 vulnerability is being actively exploited; treat it as a priority. CISA lists it as used in ransomware campaigns. The available sources name no fixed version. Check the vendor guidance in the references below. Immediate actions, mitigation and detection rules are in the runbook below.

    Affected
    • @tanstack Arktype-adapter eq 1.166.12..1.166.12
    • @tanstack Arktype-adapter eq 1.166.15..1.166.15
    • @tanstack Eslint-plugin-router eq 1.161.9..1.161.9
    • @tanstack Eslint-plugin-router eq 1.161.12..1.161.12
    • @tanstack Eslint-plugin-start eq 0.0.4..0.0.4
    • @tanstack Eslint-plugin-start eq 0.0.7..0.0.7
    • @tanstack History eq 1.161.9..1.161.9
    • @tanstack History eq 1.161.12..1.161.12
    • @tanstack Nitro-v2-vite-plugin eq 1.154.12..1.154.12
    • @tanstack Nitro-v2-vite-plugin eq 1.154.15..1.154.15
    • @tanstack React-router eq 1.169.5..1.169.5
    • @tanstack React-router eq 1.169.8..1.169.8
    • @tanstack React-router-devtools eq 1.166.16..1.166.16
    • @tanstack React-router-devtools eq 1.166.19..1.166.19
    • @tanstack React-router-ssr-query eq 1.166.15..1.166.15
    • @tanstack React-router-ssr-query eq 1.166.18..1.166.18
    • @tanstack React-start eq 1.167.68..1.167.68
    • @tanstack React-start eq 1.167.71..1.167.71
    • @tanstack React-start-client eq 1.166.51..1.166.51
    • @tanstack React-start-client eq 1.166.54..1.166.54
    • @tanstack React-start-rsc eq 0.0.47..0.0.47
    • @tanstack React-start-rsc eq 0.0.50..0.0.50
    • @tanstack React-start-server eq 1.166.55..1.166.55
    • @tanstack React-start-server eq 1.166.58..1.166.58
    • @tanstack Router-cli eq 1.166.46..1.166.46
    • @tanstack Router-cli eq 1.166.49..1.166.49
    • @tanstack Router-core eq 1.169.5..1.169.5
    • @tanstack Router-core eq 1.169.8..1.169.8
    • @tanstack Router-devtools eq 1.166.16..1.166.16
    • @tanstack Router-devtools eq 1.166.19..1.166.19
    • @tanstack Router-devtools-core eq 1.167.6..1.167.6
    • @tanstack Router-devtools-core eq 1.167.9..1.167.9
    • @tanstack Router-generator eq 1.166.45..1.166.45
    • @tanstack Router-generator eq 1.166.48..1.166.48
    • @tanstack Router-plugin eq 1.167.38..1.167.38
    • @tanstack Router-plugin eq 1.167.41..1.167.41
    • @tanstack Router-ssr-query-core eq 1.168.3..1.168.3
    • @tanstack Router-ssr-query-core eq 1.168.6..1.168.6
    • @tanstack Router-utils eq 1.161.11..1.161.11
    • @tanstack Router-utils eq 1.161.14..1.161.14
    • @tanstack Outer-vite-plugin eq 1.166.53..1.166.53
    • @tanstack Outer-vite-plugin eq 1.166.56..1.166.56
    • @tanstack Solid-router eq 1.169.5..1.169.5
    • @tanstack Solid-router eq 1.169.8..1.169.8
    • @tanstack Solid-router-devtools eq 1.166.16..1.166.16
    • @tanstack Solid-router-devtools eq 1.166.19..1.166.19
    • @tanstack Solid-router-ssr-query eq 1.166.15..1.166.15
    • @tanstack Solid-router-ssr-query eq 1.166.18..1.166.18
    • @tanstack Solid-start eq 1.167.65..1.167.65
    • @tanstack Solid-start eq 1.167.68..1.167.68
    • @tanstack Solid-start-client eq 1.166.50..1.166.50
    • @tanstack Solid-start-client eq 1.166.53..1.166.53
    • @tanstack Solid-start-server eq 1.166.54..1.166.54
    • @tanstack Solid-start-server eq 1.166.57..1.166.57
    • @tanstack Start-client-core eq 1.168.5..1.168.5
    • @tanstack Start-client-core eq 1.168.8..1.168.8
    • @tanstack Start-fn-stubs eq 1.161.9..1.161.9
    • @tanstack Start-fn-stubs eq 1.161.12..1.161.12
    • @tanstack Start-plugin-core eq 1.169.23..1.169.23
    • @tanstack Start-plugin-core eq 1.169.26..1.169.26
    • @tanstack Start-server-core eq 1.167.33..1.167.33
    • @tanstack Start-server-core eq 1.167.36..1.167.36
    • @tanstack Start-static-server-functions eq 1.166.44..1.166.44
    • @tanstack Start-static-server-functions eq 1.166.47..1.166.47
    • @tanstack Start-storage-context eq 1.166.38..1.166.38
    • @tanstack Start-storage-context eq 1.166.41..1.166.41
    • @tanstack Valibot-adapter eq 1.166.12..1.166.12
    • @tanstack Valibot-adapter eq 1.166.15..1.166.15
    • @tanstack Virtual-file-routes eq 1.161.10..1.161.10
    • @tanstack Virtual-file-routes eq 1.161.13..1.161.13
    • @tanstack Vue-router eq 1.169.5..1.169.5
    • @tanstack Vue-router eq 1.169.8..1.169.8
    • @tanstack Vue-router-devtools eq 1.166.16..1.166.16
    • @tanstack Vue-router-devtools eq 1.166.19..1.166.19
    • @tanstack Vue-router-ssr-query eq 1.166.15..1.166.15
    • @tanstack Vue-router-ssr-query eq 1.166.18..1.166.18
    • @tanstack Vue-start eq 1.167.61..1.167.61
    • @tanstack Vue-start eq 1.167.64..1.167.64
    • @tanstack Vue-start-client eq 1.166.46..1.166.46
    • @tanstack Vue-start-client eq 1.166.49..1.166.49
    • @tanstack Vue-start-server eq 1.166.50..1.166.50
    • @tanstack Vue-start-server eq 1.166.53..1.166.53
    • @tanstack Zod-adapter eq 1.166.12..1.166.12
    • @tanstack Zod-adapter eq 1.166.15..1.166.15

    Not sure whether and how you are affected? Ask a question about this vulnerability

    Metrics

    9.6

    Priority

    XIEM Effective CVSS: highest available CVSS rating from NVD and vendor data.

    Source: NVD, CVSS v3

    9.6

    CVSS v3

    Severity Critical on the scale from 0 to 10.

    Source: CVE.org, pwn.watch, EUVD, OSV

    3.3 %

    EPSS score

    Moderate — model estimates 1-10% exploitation likelihood.

    Source: FIRST EPSS, percentile 88.4

    Show all metrics
    Severity
    Critical
    Priority (0–325)

    The priority score is a consolidated metric that condenses several individual signals into a single, action-guiding ranking: technical severity (CVSS), exploitation likelihood (EPSS), known-exploited status (KEV) and the context of the affected asset. The aim is to answer the only truly important question in vulnerability management: what first?

    Read in glossary
    252.83 Methodology
    Exploit maturity

    An exploit is code or a technique that specifically uses a concrete vulnerability to force unintended behaviour — such as executing code or escalating privileges. It is the tool that turns a theoretical flaw into a practical attack.

    Read in glossary
    actively exploitedSource: VulnCheck KEV (opens in a new tab) How we classify
    XIEM Effective CVSS

    XIEM® is the tiered managed-security operating model from NEOSEC and a registered trademark of NEOSEC GmbH. It extends classic SIEM — the central collection, normalisation and correlation of security-relevant events — with endpoint forensics, network visibility and deception technology, and consolidates them into three building tiers: Sentry, Orchestrate and Command.

    Read in glossary
    9.6 Methodology
    CVSS v3

    CVSS is the globally established, open standard for assessing the technical severity of a vulnerability on a scale from 0 to 10. It describes how easily a flaw can be exploited and what damage it can cause — but not how likely its actual exploitation is. CVSS and the complementary EPSS deliberately answer different questions.

    Read in glossary
    9.6
    EPSS score

    The EPSS score is the absolute model output for an individual vulnerability: the estimated probability of real-world exploitation within the next 30 days, expressed as a value between 0 and 1 (i.e. 0 % to 100 %). A score of 0.42 means „the model estimates a 42 % chance of real-world exploitation within 30 days“.

    Read in glossary
    3.3 %
    Moderate — model estimates 1-10% exploitation likelihood.
    EPSS percentile

    The EPSS percentile is the relative position of a vulnerability within all EPSS-scored CVEs, expressed as a value between 0 and 1. A percentile of 0.90 means „this CVE has a higher EPSS score than 90 % of all other scored CVEs“. Unlike the EPSS score, it is not a probability — but a positioning within a ranking.

    Read in glossary
    88.4
    Critical — this CVE ranks in the top fifth of all CVEs scored today (rank ≥ 80%).
    KEV status

    The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching.

    Read in glossary
    Actively exploited
    Published
    In CISA KEV since

    The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching.

    Read in glossary
    CWE

    CWE is a catalogue of typical weakness types in software and hardware — such as flawed input validation, unsafe memory handling or poor authentication. Where a CVE names a concrete vulnerability in a concrete product, a CWE describes the underlying class of defect.

    Read in glossary
    CWE-506

    Response and mitigation

    Why act now?

    Prioritisation rationale

    This entry reflects a real supply-chain attack: a legitimate OIDC trusted-publisher binding was abused to ship credential-stealing releases under a trusted identity, harvesting secrets from developer and CI environments. CISA flags known ransomware use, so stolen tokens are a realistic initial-access vector for follow-on attacks on source code, cloud tenants and production. The flaw is network-reachable without authentication, needs only a user-triggered install and has scope-changing impact. Its statistical exploitation likelihood is only moderate, but that matters little for a publish incident that has already happened. What counts is whether an affected version was installed during the window: if so, treat it as top priority with full credential rotation and a NIS2 reporting assessment; if not, blocking the versions and hardening the build pipeline is sufficient.

    1. Runbook step 1

      Immediate response (0-24 h)

      • Inventory affected versions: Scan all lockfiles (package-lock.json, yarn.lock, pnpm-lock.yaml), artifact repositories (Artifactory/Nexus/Verdaccio) and container images for @tanstack/*. Known malicious versions include @tanstack/arktype-adapter 1.166.12 and 1.166.15, @tanstack/eslint-plugin-router 1.161.9 and 1.161.12, @tanstack/eslint-plugin-start 0.0.4 and 0.0.7, and @tanstack/history 1.161.9 and 1.161.12. In total, 84 versions across 42 packages are affected. Pull the full list from the TanStack/GitHub security advisory.
      • Scope compromised hosts: Treat every developer workstation, CI runner and build container that installed an affected version from 2026-05-11 19:20 UTC onward as compromised. Isolate persistent/self-hosted runners and do not reuse ephemeral runners.
      • Rotate credentials now: The payload is built to steal credentials. On every affected host, revoke and reissue npm tokens (~/.npmrc), GitHub PATs, SSH keys, cloud credentials (AWS/Azure/GCP), .env secrets and CI secrets. Kill active sessions.
      • Block the malicious versions: Deny the affected versions in your registry proxy and pin to a release the vendor has confirmed as clean. Check the vendor advisory for the exact version. Then purge node_modules and the npm/pnpm/yarn cache and rebuild with npm ci.
      • Review shipped artefacts: Inspect builds produced from an affected lockfile during the window for bundled malicious code, and recall them where needed.

    2. Runbook step 2

      Mitigation layers

      • Supply chain / registry: Route all npm traffic through an internal proxy. Enforce a quarantine or minimum-age policy for new package versions (e.g. pnpm minimumReleaseAge, curation rules in Artifactory/Nexus), so freshly published malicious releases never reach your builds.
      • Build hardening: Use only npm ci against a committed lockfile in CI. Disable lifecycle scripts by default (npm config set ignore-scripts true) and allowlist them only for explicitly approved packages.
      • Network segmentation: Restrict CI runners and build containers with an egress allowlist covering the registry proxy, SCM and artefact targets. Block and log all other outbound traffic to stop exfiltration.
      • Harden your own GitHub Actions (same attack classes): Do not run pull_request_target workflows that check out or execute fork code. Separate the Actions cache between fork and base contexts, and never let untrusted workflows populate cache keys. Grant id-token: write only to the publish job, and bind trusted publishers to protected branches/environments.
      • IAM / least privilege: Replace long-lived npm and cloud tokens on developer machines with short-lived, narrowly scoped tokens. Require 2FA or environment approvals for publish rights.

    3. Runbook step 3

      Detection rules

      • SCA/lockfile sweep: grep -RnE '@tanstack/(history|eslint-plugin-router)@?"?:? ?"?1\.161\.(9|12)' --include='*lock*', plus equivalent patterns for the other packages. Alternatively, run npm ls @tanstack/history @tanstack/arktype-adapter @tanstack/eslint-plugin-router @tanstack/eslint-plugin-start --all and match the results against the advisory list.
      • EDR process ancestry: Look for npm/node → sh/cmd.exe/powershell.exe → curl/wget/node -e during an install. KQL: DeviceProcessEvents | where InitiatingProcessCommandLine has_any ("npm install","npm ci","pnpm","yarn") and FileName in~ ("curl","wget","powershell.exe","bash","sh").
      • Credential-file access: Use auditd with -w /home/<user>/.npmrc -p r -k npmrc_read, plus similar rules for ~/.aws/credentials, ~/.ssh/ and ~/.config/gh/. On Windows, use Sysmon EID 10/11 or EDR file events showing node.exe reading the same paths. Alert on reads by node outside normal tooling.
      • Network telemetry: In Zeek/Suricata or proxy logs, look for outbound connections from build hosts to unfamiliar domains/IPs shortly after package installs, especially POST requests with large bodies. Also check Sysmon EID 3 with Image = node.exe.
      • SaaS audit logs: Review the GitHub audit log (new PATs, deploy keys, unexpected workflow runs, repo clones) and the npm account log (new tokens, publishes) from 2026-05-11 onward for misuse of stolen credentials.

    Detection rules

    No NEOSEC detection rule is available for this vulnerability yet.

    Classification under NIS2 and CRA

    Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.

    NIS2

    NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management.

    Read in glossary
    Actively exploited: treat the vulnerability as a priority in vulnerability handling under Art. 21(2)(e) NIS2. If it is exploited in your environment, check the reporting obligation under Art. 23 (early warning within 24 hours).
    CRA

    The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates.

    Read in glossary
    Since 11.09.2026, manufacturers of affected products with digital elements must report actively exploited vulnerabilities under Art. 14 CRA, with an early warning within 24 hours via ENISA's single reporting platform.
    ISO/IEC 27001

    ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security.

    Read in glossary
    Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.

    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.

    Source: NVD (NIST), pwn.watch, CISA KEV Catalog, cvelistv5, ENISA EUVD, CVE.org (MITRE), OSV (Open Source Vulnerabilities)

    Affected products

    The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.

    Affected products
    Affected versionsFixed in
    @tanstackarktype-adapter
    • 1.166.12
    • 1.166.15
    • —
    • —
    @tanstackeslint-plugin-router
    • 1.161.9
    • 1.161.12
    • —
    • —
    @tanstackeslint-plugin-start
    • 0.0.4
    • 0.0.7
    • —
    • —
    @tanstackhistory
    • 1.161.9
    • 1.161.12
    • —
    • —
    @tanstacknitro-v2-vite-plugin
    • 1.154.15
    • 1.154.12
    • —
    • —
    @tanstackouter-vite-plugin
    • 1.166.53
    • 1.166.56
    • —
    • —
    @tanstackreact-router
    • 1.169.5
    • 1.169.8
    • —
    • —
    @tanstackreact-router-devtools
    • 1.166.19
    • 1.166.16
    • —
    • —
    @tanstackreact-router-ssr-query
    • 1.166.18
    • 1.166.15
    • —
    • —
    @tanstackreact-start
    • 1.167.71
    • 1.167.68
    • —
    • —
    @tanstackreact-start-client
    • 1.166.51
    • 1.166.54
    • —
    • —
    @tanstackreact-start-rsc
    • 0.0.47
    • 0.0.50
    • —
    • —
    @tanstackreact-start-server
    • 1.166.55
    • 1.166.58
    • —
    • —
    @tanstackrouter-cli
    • 1.166.46
    • 1.166.49
    • —
    • —
    @tanstackrouter-core
    • 1.169.8
    • 1.169.5
    • —
    • —
    @tanstackrouter-devtools
    • 1.166.16
    • 1.166.19
    • —
    • —
    @tanstackrouter-devtools-core
    • 1.167.6
    • 1.167.9
    • —
    • —
    @tanstackrouter-generator
    • 1.166.45
    • 1.166.48
    • —
    • —
    @tanstackrouter-plugin
    • 1.167.41
    • 1.167.38
    • —
    • —
    @tanstackrouter-ssr-query-core
    • 1.168.3
    • 1.168.6
    • —
    • —
    @tanstackrouter-utils
    • 1.161.11
    • 1.161.14
    • —
    • —
    @tanstacksolid-router
    • 1.169.8
    • 1.169.5
    • —
    • —
    @tanstacksolid-router-devtools
    • 1.166.19
    • 1.166.16
    • —
    • —
    @tanstacksolid-router-ssr-query
    • 1.166.15
    • 1.166.18
    • —
    • —

    Vendors and products

    Weakness classes (CWE)

    • CWE-506Embedded Malicious Code

      Class

      The product contains code that appears to be malicious in nature.

      Entry at MITRE CWE-506

    Public exploit references

    Publicly reported proof-of-concepts, exploit modules and detection templates for this vulnerability. NEOSEC links to the original sources only and does not provide any exploit code.

    Public exploit references
    CISA KEV CatalogCISA Known Exploited Vulnerability (opens in a new tab)cisa.govactively exploited
    PoC-in-GitHub (nomi-sec)mini-shai-hulud-detector (opens in a new tab)github.comPoC (publicly reported)reported, not verified
    PoC-in-GitHub (nomi-sec)tanscript-exploit-check (opens in a new tab)github.comPoC (publicly reported)reported, not verified

    References & sources

    • github.comTanStack/router/security/advisories/GHSA-g7cv-rxg3-hmpxweb, x_refsource_CONFIRM, Mitigation, Vendor advisory, pwn-watch
    • NVD (NIST)NVD: CVE-2026-45321advisory, pwn-watch
    • github.comTanStack/router/issues/7383web, x_refsource_MISC, Issue tracking
    • github.comTanStack/routerpackage
    • socket.devblog/tanstack-npm-packages-compromised-mini-shai-hulud-supply-c…web
    • tanstack.comblog/npm-supply-chain-compromise-postmortemweb, x_refsource_MISC, Exploit, Vendor advisory
    • cisa.govknown-exploited-vulnerabilities-catalog?field_cve=CVE-2026-45321web, government-resource, US government resource
    • stepsecurity.ioblog/mini-shai-hulud-is-back-a-self-spreading-supply-chain-atta…web, x_refsource_MISC, Exploit, Third-party advisory
    • pwn.watchpwn.watch: TanStack TanStack: TanStack Unspecified Vulnerabilitypwn-watch
    • cisa.govCISA Known Exploited Vulnerabilities Catalogpwn-watch

    Changes to this CVE

    Who changed this CVE and when: NVD (analysis, affected products, CVSS), the CVE publisher (CNA) and additional providers such as CISA (ADP).

    One NVD translation into another language is hidden.

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