OpenBao lacks user confirmation for OIDC direct callback mode

Critical9.6CVE-2026-33757 · Published Mar 26, 2026 · updated Jul 27, 2026

### Impact OpenBao does not prompt for user confirmation when logging in via JWT/OIDC and a role with `callback_mode` set to `direct`. This allows an attacker to start an authentication request and perform "remote phishing" by having the victim visit the URL and automatically log-in to the session of the attacker. Despite being based on the authorization code flow, the `direct` mode calls back directly to the API and allows an attacker to poll for an OpenBao token until it is issued. ### Patches Version 2.5.2 includes an additional confirmation screen for `direct` type logins that requires manual user interaction in order to finish the authentication. ### Workarounds This issue can be worked around either by removing any roles with `callback_mode=direct` or enforcing confirmation for every session on the token issuer side for the Client ID used by OpenBao.