`signInWithEmailAndPassword` suddenly fails due to a CORS error (403)

[yanoyuki]

Operating System

Mac / Windows

Environment (if applicable)

Chrome, node20

Firebase SDK Version

9.22.1

Firebase SDK Product(s)

Auth

Project Tooling

React app with Vite

Detailed Problem Description

While attempting to sign in using the method below:

signInWithEmailAndPassword(auth, email, password)

Some users have started experiencing a CORS error today.

This issue seems to affect only a subset of users, while others are able to sign in and sign up successfully without any problems.

Other authentication methods and Firebase services, such as Firestore, are functioning correctly. It appears that only signInWithEmailAndPassword is failing.

Steps and code to reproduce issue

Call

signInWithEmailAndPassword(auth, email, password)

[google-oss-bot]

I couldn't figure out how to label this issue, so I've labeled it for a human to triage. Hang tight.

[yanoyuki]

[yanoyuki]

I confirmed that the issue has been resolved, even though no changes were made to the application itself.