TanStack TanStack
CVE-2026-45321
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.
What this means for your business
- It affects TanStack. It matters if your company, or a supplier that handles your data, runs it.
- Attackers are already using it. CISA added it to its list of flaws used in real attacks on 27 May 2026.
- Ransomware gangs are known to have used it.
- FIRST's prediction model gives it a 3% chance of attack attempts being seen in the next 30 days, ranking above 88% of all known flaws.
What to do
- 1Check whether your company or your suppliers run TanStack.
- 2If you do, follow CISA's required action below. No patch reference has been published yet.
- 3Treat it as urgent. US federal agencies must fix it by 10 June 2026. That deadline does not apply to private companies, but it shows how seriously CISA takes it.
- 4Because attackers have used it, check the affected systems for signs of a break-in, not only for the update.
Fastnexa security experts
Attackers are already using this flaw. Is your TanStack TanStack exposed?
Tell us where you run TanStack TanStack and a Fastnexa penetration tester will check whether this flaw, or others like it, can be used against your websites, apps and network.
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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.
CISA’s wording, unedited.
Scoring
- CVSS
- Not yet scored
Dates
- Published
- 2026-05-27
- Added to KEV
- 2026-05-27
- Remediation due
- 2026-06-10
- Sources
- CISA KEV