Description
The Auth0 Next.js SDK is a library for implementing user authentication in Next.js applications. Versions 4.9.0 through 4.12.1 contain an input-validation flaw in the returnTo parameter, which could allow attackers to inject unintended OAuth query parameters into the Auth0 authorization request. Successful exploitation may result in tokens being issued with unintended parameters. This issue is fixed in version 4.13.0.
Scores
CVSS v3
5.7
EPSS
0.0008
EPSS Percentile
22.7%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:H/I:H/A:N
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
partial
Details
CWE
CWE-184
Status
published
Products (2)
auth0/nextjs-auth0
4.9.0 - 4.12.1
auth0/nextjs-auth0
4.9.0 - 4.13.0npm
Published
Dec 11, 2025
Tracked Since
Feb 18, 2026