Applications that use next-auth
Email Provider and @next-auth/upstash-redis-adapter
before v3.0.2 are affected.
The Upstash Redis adapter implementation did not check for both the identifier (email) and the token, but only checking for the identifier when verifying the token in the email callback flow. An attacker who knows about the victim's email could easily sign in as the victim, given the attacker also knows about the verification token's expired duration.
The vulnerability is patched in v3.0.2. To upgrade, run one of the following:
npm i @next-auth/upstash-redis-adapter@latest
yarn add @next-auth/upstash-redis-adapter@latest
pnpm add @next-auth/upstash-redis-adapter@latest
Using Advanced Initialization, developers can check the requests and compare the query's token and identifier before proceeding. Below is an example of how to do this: (Upgrading is still strongly recommended)
import { createHash } from "crypto"
export default async function auth(req, res) {
if (req.method === "POST" && req.action === "callback") {
const token = req.query?.token
const identifier = req.query?.email
function hashToken(token: string) {
const provider = authOptions.providers.find((p) => p.id === "email")
const secret = authOptions.secret
return (
createHash("sha256")
// Prefer provider specific secret, but use default secret if none specified
.update(`${token}${provider.secret ?? secret}`)
.digest("hex")
)
}
const hashedToken = hashToken(token)
const invite = await authOptions.adapter.useVerificationToken?.({
identifier,
token: hashedToken,
})
if (invite.token !== hashedToken) {
res.status(400).json({ error: "Invalid token" })
}
}
return await NextAuth(req, res, authOptions)
}
EmailProvider: https://next-auth.js.org/providers/email Advanced Initialization: https://next-auth.js.org/configuration/initialization#advanced-initialization Upstash Redis Adapter: https://next-auth.js.org/adapters/upstash-redis
If you have any concerns, we request responsible disclosure, outlined here: https://next-auth.js.org/security#reporting-a-vulnerability