CVE-2026-102989 TanStack Router - Stored XSS

TanStack Router versions @tanstack/start-server-core 1.143.12 to <1.169.39, @tanstack/react-start <1.168.60, @tanstack/solid-start <1.168.57, and @tanstack/vue-start <1.168.56 contain a stored XSS caused by attacker-controlled middleware state reaching error path, letting unauthenticated attackers inject scripts that execute with visitor's authority, exploit requires crafted server-function URL.

CVSS base score 9.3 /10
Critical
CISA KEV
Not listed
Public exploit
None known
Authentication
Not required
EPSS
0.52% chance of exploitation in 30 days
View the NVD record ↗

Details

Type
Stored XSS
Impact
Stored XSS, Information Disclosure
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N
Published
13 October 2026
Updated
15 October 2026
Weakness
CWE-79

Vendor fix

Update to @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 or later.

Patching closes this CVE. It does not tell you which of your systems run the affected version, or what else is exposed alongside them.

References

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