[macOS/iPhone][Remote] QR re-auth rejects correct password before MFA challenge

What version of the Codex App are you using?

Latest available version as of 2026-09-09 on macOS. The iPhone ChatGPT/Codex app is also updated to the latest available version.

What platform are you using?

• Host: macOS
• Remote client: iPhone / iOS

What issue are you seeing?

Codex Remote Connection pairing cannot complete when the ChatGPT account has two-factor / multi-factor authentication enabled.

The account password is valid. In a normal login flow on the Mac, entering the same password succeeds and the login correctly proceeds to the second-factor verification step. After completing the second factor, login succeeds.

However, when setting up Codex Remote Connection by scanning the QR code with the iPhone, the re-authentication flow behaves differently:

1. The QR code is scanned from the iPhone.
2. A username/password authentication screen is shown.
3. The correct account password is entered.
4. Instead of proceeding to the MFA / 2FA challenge, the flow immediately reports that the password is incorrect / authentication failed.
5. There is no opportunity to enter the second-factor code.

This makes Remote pairing impossible even though the exact same password works in the normal ChatGPT/Codex login flow and successfully reaches MFA verification there.

Steps to reproduce

1. Use a ChatGPT account with MFA / 2FA enabled.
2. Confirm that a normal login on macOS works as expected:
   • enter the account password;
   • password is accepted;
   • complete the second-factor challenge;
   • login succeeds.
3. Open Codex Remote Connection setup on the Mac and generate the pairing QR code.
4. Scan the QR code with the ChatGPT/Codex app on iPhone.
5. When the re-authentication screen asks for username/password, enter the same known-good password.
6. Observe that the flow immediately reports a password/authentication error instead of proceeding to MFA.

Expected behavior

After the correct password is entered during Remote Connection re-authentication, the flow should continue to the account's configured MFA / 2FA challenge. After successful second-factor verification, Remote pairing should continue.

Expected sequence:

QR scan -> password accepted -> MFA challenge -> MFA accepted -> Remote pairing

Actual behavior

The Remote re-authentication flow stops after password entry and incorrectly reports a password/authentication failure. The MFA challenge is never shown.

Actual sequence:

QR scan -> correct password -> password/authentication error

Why this appears to be an MFA/re-auth flow issue

The password itself is independently verified to be correct because the normal login flow accepts it and then requests the configured second factor.

The failure only occurs inside the QR-code Remote Connection re-authentication path, and specifically before the MFA challenge is presented. This suggests the Remote re-authentication flow may be failing to transition from password verification to the MFA challenge, or may be mapping an MFA-required response to a generic/incorrect password error.

Environment / checks

• macOS host
• iPhone remote client
• Codex / ChatGPT apps are updated to the latest available versions on both devices
• Account has MFA / 2FA enabled
• Correct password is accepted by the normal login flow
• Normal login correctly proceeds to second-factor verification
• Remote QR re-authentication does not present the second-factor step

Related issues

Possibly related, but the user-visible failure here is distinct:

• #24328 — iPhone Codex remote control setup fails until desktop session satisfies MFA
• #41747 — Codex Remote Control rejects verified MFA login
• #40463 — Remote Connection re-auth password-only flow for Sign in with Apple accounts

In this report, the account has a working password and normal password + MFA login succeeds. The problem is that the Remote QR re-auth path rejects the known-good password before allowing the MFA challenge.

Suggested product behavior / diagnostics

If the backend indicates that MFA is required after primary credential verification, the Remote setup UI should explicitly continue to the MFA challenge rather than surface a password error.

If the MFA transition itself fails, the UI should distinguish that from an invalid password, for example:

Additional verification is required to continue Remote Connection setup.

It would also help if Remote diagnostics exposed whether the failure occurred at:

• primary password verification,
• MFA challenge creation,
• MFA verification, or
• Remote enrollment.

No passwords, MFA codes, account identifiers, or other credentials are included in this report.

Start by reproducing the QR pairing re-authentication flow with an MFA-enabled account and compare it with the normal macOS login sequence. Trace how the Remote flow handles the password-verification response and MFA transition; done means a valid password presents the MFA challenge and successful verification completes Remote pairing.