diff --git a/backend/open_webui/models/auths.py b/backend/open_webui/models/auths.py
index 01ac873696..418d5c5479 100644
--- a/backend/open_webui/models/auths.py
+++ b/backend/open_webui/models/auths.py
@@ -3,13 +3,12 @@
 from __future__ import annotations
 
 import logging
-import time
 import uuid
 from typing import Optional
 
 import bcrypt
 from open_webui.internal.db import Base, JSONField, get_async_db_context
-from open_webui.models.users import User, UserModel, UserProfileImageResponse, Users
+from open_webui.models.users import UserModel, UserProfileImageResponse, Users
 from open_webui.utils.validate import validate_profile_image_url
 from pydantic import BaseModel, field_validator
 from sqlalchemy import Boolean, Column, String, Text, delete, select, update
@@ -111,13 +110,12 @@ class AuthsTable:
         role: str = 'pending',
         oauth: dict | None = None,
         db: AsyncSession | None = None,
-        user_id: str | None = None,
     ) -> UserModel | None:
         """Create an Auth + User pair inside a single transaction."""
         async with get_async_db_context(db) as session:
             log.info('insert_new_auth')
 
-            new_id = user_id or str(uuid.uuid4())
+            new_id = str(uuid.uuid4())
 
             credential = Auth(
                 id=new_id,
@@ -128,25 +126,15 @@ class AuthsTable:
             session.add(credential)
 
             try:
-                profile_image_url = validate_profile_image_url(profile_image_url)
-            except ValueError:
-                profile_image_url = '/user.png'
-
-            now = int(time.time())
-            created_user = UserModel(
-                id=new_id,
-                email=email,
-                name=name,
-                role=role,
-                profile_image_url=profile_image_url,
-                last_active_at=now,
-                created_at=now,
-                updated_at=now,
-                oauth=oauth,
-            )
-            session.add(User(**created_user.model_dump()))
-
-            try:
+                created_user = await Users.insert_new_user(
+                    new_id,
+                    name,
+                    email,
+                    profile_image_url,
+                    role,
+                    oauth=oauth,
+                    db=session,
+                )
                 await session.commit()
             except IntegrityError:
                 await session.rollback()
diff --git a/backend/open_webui/routers/auths.py b/backend/open_webui/routers/auths.py
index a5f4bca140..d9f6b022ba 100644
--- a/backend/open_webui/routers/auths.py
+++ b/backend/open_webui/routers/auths.py
@@ -2,8 +2,6 @@ from __future__ import annotations
 
 import asyncio
 import datetime
-import hashlib
-import hmac
 import logging
 import re
 import time
@@ -38,7 +36,6 @@ from open_webui.env import (
     WEBUI_AUTH_TRUSTED_GROUPS_HEADER,
     WEBUI_AUTH_TRUSTED_NAME_HEADER,
     WEBUI_AUTH_TRUSTED_ROLE_HEADER,
-    WEBUI_SECRET_KEY,
 )
 from open_webui.internal.db import get_async_session
 from open_webui.models.auths import (
@@ -104,15 +101,6 @@ token_exchange_rate_limiter = (
 )
 
 
-def trusted_header_user_id(email: str) -> str:
-    digest = hmac.digest(
-        WEBUI_SECRET_KEY.encode(),
-        f'open-webui:trusted-header:{email.lower()}'.encode(),
-        hashlib.sha256,
-    )
-    return str(uuid.UUID(bytes=digest[:16], version=4))
-
-
 ADMIN_CONFIG_KEYS = {
     'SHOW_ADMIN_DETAILS': 'auth.admin.show',
     'ADMIN_EMAIL': 'auth.admin.email',
@@ -761,7 +749,6 @@ async def signin(
                     name,
                     db=db,
                     source='trusted_header',
-                    user_id=trusted_header_user_id(email),
                 )
             except IntegrityError:
                 if not await Users.get_user_by_email(email.lower(), db=db):
@@ -846,7 +833,6 @@ async def signup_handler(
     *,
     db: AsyncSession,
     source: str = 'api',
-    user_id: str | None = None,
 ) -> UserModel:
     """
     Core user-creation logic shared by the signup endpoint and
@@ -867,7 +853,6 @@ async def signup_handler(
         profile_image_url=profile_image_url,
         role=await Config.get('ui.default_user_role'),
         db=db,
-        user_id=user_id,
     )
     if not user:
         raise HTTPException(500, detail=ERROR_MESSAGES.CREATE_USER_ERROR)