Description
The auth0/nextjs-auth0 SDK validates that the returnTo parameter is a same-origin URL. The SDK then stores this value and, in a later step, reconstructs it for the post-authentication redirect. The reconstruction logic can produce a URL that browsers interpret as an absolute or scheme-relative path, leading to a redirect to an unintended domain.
References2
Metrics
- CVSS 3.1
-
6.1
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - EPSS — exploit probability
- 0% percentile: 13 · as of 11 November 2026
- CWE
- CWE-601
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