fix: prevent open redirect in redirect_uri validation#542
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lakhansamani merged 2 commits intomainfrom Apr 3, 2026
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When allowed_origins=* (the default), IsValidOrigin() accepted any URL as a valid redirect_uri, enabling attackers to steal password reset tokens, magic link tokens, and OAuth tokens by redirecting users to attacker-controlled domains. Add IsValidRedirectURI() that never accepts * as a blanket pass. When allowed_origins=*, only self-origin redirects are allowed. Also add redirect_uri validation to /logout and /authorize which had none. Fixes #540
Cover *.example.com patterns, port-specific wildcards, multi-origin with wildcards, and bypass attempts like example.com.attacker.com.
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Summary
IsValidRedirectURI()that never accepts*as a blanket pass for redirect URIs (unlikeIsValidOriginused for CORS)allowed_origins=*(default config), only self-origin redirects are permitted/logoutand/authorizewhich previously had noneIsValidOrigintoIsValidRedirectURIjavascript:,data:,ftp:) in redirect URIsAffected Endpoints (9 total)
forgot_passwordIsValidOrigin(bypassed with*)IsValidRedirectURImagic_link_loginIsValidOrigin(bypassed with*)IsValidRedirectURIsignupIsValidOrigin(bypassed with*)IsValidRedirectURIinvite_membersIsValidOrigin(bypassed with*)IsValidRedirectURI/verify_emailIsValidOrigin(bypassed with*)IsValidRedirectURI/oauth/loginIsValidOrigin(bypassed with*)IsValidRedirectURI/appIsValidOrigin(bypassed with*)IsValidRedirectURI/logoutIsValidRedirectURI/authorizeIsValidRedirectURITest plan
IsValidRedirectURI(wildcard, explicit origins, non-HTTP schemes, port matching)IsValidOrigintests unaffected (CORS behavior unchanged)Fixes #540