Critical severity · published May 12, 2026
CVE-2026-45321
Malware in 42 @tanstack/* packages exfiltrates cloud credentials, GitHub tokens, and SSH keys
RansomwareIn wildKEV
9.6
CVSS
3.3%
EPSS
Yes
On KEV
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 vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)3.3% · higher than 88% of CVEs
Exploited in the wildYes
CISA KEVListed May 27, 2026
Federal remediation dueJun 10, 2026
Ransomware campaign useKnown
Affected products
Which versions
AR
arktype-adapter · @tanstack
1.166.12; 1.166.15 · source: vendor
ES
eslint-plugin-router · @tanstack
1.161.9; 1.161.12 · source: vendor
ES
eslint-plugin-start · @tanstack
0.0.4; 0.0.7 · source: vendor
HI
history · @tanstack
1.161.9; 1.161.12 · source: vendor
NI
nitro-v2-vite-plugin · @tanstack
1.154.12; 1.154.15 · source: vendor
OU
outer-vite-plugin · @tanstack
1.166.53; 1.166.56 · source: vendor
RE
react-router · @tanstack
1.169.5; 1.169.8 · source: vendor
RE
react-router-devtools · @tanstack
1.166.16; 1.166.19 · source: vendor
RE
react-router-ssr-query · @tanstack
1.166.15; 1.166.18 · source: vendor
RE
react-start · @tanstack
1.167.68; 1.167.71 · source: vendor
RE
react-start-client · @tanstack
1.166.51; 1.166.54 · source: vendor
RE
react-start-rsc · @tanstack
0.0.47; 0.0.50 · source: vendor
In the news
VulnerabilityCritical
CISA Adds Three Known Exploited Vulnerabilities to Catalog
CISA has added three new vulnerabilities to its  Known Exploited Vulnerabilities (KEV) Catalog , based on evidence of active exploitation. CVE-2026-8398  Daemon Tools Lite Embedded Malicious Code Vulnerability CVE-2026-45321  TanStack Unspecified Vulnerability CVE-2026-48027  Nx Console Embedded Malicious Code Vulnerability These types of vulnerabilities are frequent attack vectors for malicious cyber actors and pose significant risks to the federal enterprise. Binding Operational Directive (BOD) 22-01: Reducing the Significant Risk of Known Exploited Vulnerabilities  established the KEV Catalog as a living list of known Common Vulnerabilities and Exposures (CVEs) that carry significant risk to the federal enterprise. BOD 22-01 requires Federal Civilian Executive Branch (FCEB) agencies to remediate identified vulnerabilities by the due date to protect FCEB networks against active threats. See the  BOD 22-01 Fact Sheet  for more information. Although BOD 22-01 only applies to FCEB agencies, CISA strongly urges all organizations to reduce their exposure to cyberattacks by prioritizing timely remediation of  KEV Catalog vulnerabilities  as part of their vulnerability management practice. CISA will continue to add vulnerabilities to the catalog that meet the  specified criteria .
May 27, 2026·CISA Advisories
VulnerabilityHigh
[CISA KEV] CVE-2026-45321: TanStack TanStack - TanStack Unspecified Vulnerability
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.
TATanStackCVE-2026-45321
May 27, 2026·CISA KEV