TanStack Router: Unauthenticated reflected XSS in TanStack Start server-function responses
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.
CVE-2026-102989
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-102989
router
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
react-start
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
solid-start
Source reference: /containers/cna/affected/2/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
start-server-core
Source reference: /containers/cna/affected/3/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
vue-start
Source reference: /containers/cna/affected/4/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"vendor": "TanStack",
"product": "router",
"versions": [
{
"status": "affected",
"version": "< release-2026-09-30-1747"
}
]
},
{
"vendor": "@tanstack",
"product": "react-start",
"versions": [
{
"status": "affected",
"version": ">= 1.143.12, < 1.168.60"
}
]
},
{
"vendor": "@tanstack",
"product": "solid-start",
"versions": [
{
"status": "affected",
"version": ">= 1.143.12, < 1.168.57"
}
]
},
{
"vendor": "@tanstack",
"product": "start-server-core",
"versions": [
{
"status": "affected",
"version": ">= 1.143.12, < 1.169.39"
}
]
},
{
"vendor": "@tanstack",
"product": "vue-start",
"versions": [
{
"status": "affected",
"version": ">= 1.143.12, < 1.168.56"
}
]
}
]- Related CVEs
- CVE-2026-102989
Source reference:
/cveMetadata/cveId
Publisher severity
critical
Source reference: /containers/cna/metrics
- Event
- #22068 · Revision 1
- Added to Heist Feed
- Publisher date