CVE-2026-102989 · GHSA-qx66-fv34-fjm8
TanStack Router: Unauthenticated reflected XSS in TanStack Start server-function responses
- Risk score
- 74/100
- CVSS
- 9.3 v3.1
- Exploit chance (30 days)
- 0.5%
- Published
- 13 Oct 2026
Open in the live forecast Today's forecast
What to know
- What it is
- TanStack Router is a client-first, server-capable, fully type-safe router and full-stack framework for the web. From 1.143.12 until 1.169.39 for @tanstack/start-server-core, 1.168.60 for @tanstack/react-start, 1.168.57 for @tanstack/solid-start, and 1.168.56 for @tanstack/vue-start, an unauthenticated attacker can pla…
- Affected
- @tanstack/start-server-core (npm) >= 1.143.12, < 1.169.39; @tanstack/react-start (npm) >= 1.143.12, < 1.168.60; @tanstack/solid-start (npm) >= 1.143.12, < 1.168.57; @tanstack/vue-start (npm) >= 1.143.12, < 1.168.56
- Fix
- Upgrade @tanstack/start-server-core to 1.169.39; @tanstack/react-start to 1.168.60; @tanstack/solid-start to 1.168.57; @tanstack/vue-start to 1.168.56 or later.
- Exploitation
- No known exploitation
Why it is Amber
- CVSS 9.3 critical
- Remotely exploitable without logging in
- On your watchlist: npm
Affected packages
| Package | Ecosystem | Vulnerable | Fixed in |
|---|---|---|---|
| @tanstack/start-server-core | npm | >= 1.143.12, < 1.169.39 | 1.169.39 |
| @tanstack/react-start | npm | >= 1.143.12, < 1.168.60 | 1.168.60 |
| @tanstack/solid-start | npm | >= 1.143.12, < 1.168.57 | 1.168.57 |
| @tanstack/vue-start | npm | >= 1.143.12, < 1.168.56 | 1.168.56 |
References
- https://github.com/advisories/GHSA-qx66-fv34-fjm8
- https://github.com/TanStack/router/security/advisories/GHSA-qx66-fv34-fjm8
- https://nvd.nist.gov/vuln/detail/CVE-2026-102989
- https://github.com/TanStack/router/pull/8573
- https://github.com/TanStack/router/commit/d521abd71c69f1ff010bb3def4d417cb5fa058cb
- https://github.com/TanStack/router/releases/tag/release-2026-09-30-1747
- https://github.com/advisories/GHSA-qx66-fv34-fjm8
Original description
TanStack Router is a client-first, server-capable, fully type-safe router and full-stack framework for the web. From 1.143.12 until 1.169.39 for @tanstack/start-server-core, 1.168.60 for @tanstack/react-start, 1.168.57 for @tanstack/solid-start, and 1.168.56 for @tanstack/vue-start, an unauthenticated attacker can place non-public fields in a server-function request payload so that attacker-controlled middleware state reaches the error path and a response-shaped object is accepted as an HTTP response. A crafted server-function URL can therefore return attacker-controlled HTML from the application's origin; when a visitor opens the URL, the injected script can access same-origin data and issue requests with the visitor's authority. This issue is fixed in @tanstack/start-server-core 1.169.39, @tanstack/react-start 1.168.60, @tanstack/solid-start 1.168.57, and @tanstack/vue-start 1.168.56.
Last activity 13 Oct 2026. Patch Forecast updates every hour.