diff --git a/backend/handler/auth/middleware/csrf_middleware.py b/backend/handler/auth/middleware/csrf_middleware.py
index d6a04466e..902532572 100644
--- a/backend/handler/auth/middleware/csrf_middleware.py
+++ b/backend/handler/auth/middleware/csrf_middleware.py
@@ -134,7 +134,7 @@ class CSRFMiddleware:
         return cast(str, self.serializer.dumps(obj))
 
     def _csrf_tokens_match(
-        self, document_cookie: str, header_cookie: str, user_id: str | None
+        self, document_cookie: str, header_cookie: str, user_id: int | None
     ) -> bool:
         try:
             decoded_doc_cookie: str = self.serializer.loads(document_cookie)
diff --git a/backend/tests/handler/auth/test_csrf_middleware.py b/backend/tests/handler/auth/test_csrf_middleware.py
new file mode 100644
index 000000000..8ec8fadbc
--- /dev/null
+++ b/backend/tests/handler/auth/test_csrf_middleware.py
@@ -0,0 +1,248 @@
+import re
+
+from itsdangerous import URLSafeSerializer
+from starlette.applications import Starlette
+from starlette.middleware import Middleware
+from starlette.middleware.authentication import AuthenticationMiddleware
+from starlette.requests import Request
+from starlette.responses import JSONResponse, PlainTextResponse
+from starlette.routing import Route
+from starlette.testclient import TestClient
+
+from config import ROMM_AUTH_SECRET_KEY
+from handler.auth.constants import ALGORITHM
+from handler.auth.hybrid_auth import HybridAuthBackend
+from handler.auth.middleware.csrf_middleware import CSRFMiddleware
+from handler.auth.middleware.session_middleware import SessionMiddleware
+
+
+# Test app factory                                                            #
+def create_test_app(**csrf_kwargs) -> Starlette:
+    """Return a Starlette app wired with CSRFMiddleware."""
+
+    async def get_handler(request: Request) -> PlainTextResponse:
+        return PlainTextResponse("OK")
+
+    async def post_handler(request: Request) -> JSONResponse:
+        return JSONResponse({"status": "success"})
+
+    async def post_echo(request: Request) -> JSONResponse:
+        """Return the CSRF token that was sent."""
+        token = request.headers.get(csrf_kwargs.get("header_name", "x-csrftoken"))
+        return JSONResponse({"token": token})
+
+    routes = [
+        Route("/get", get_handler, methods=["GET"]),
+        Route("/post", post_handler, methods=["POST"]),
+        Route("/echo", post_echo, methods=["POST"]),
+    ]
+    middleware = [
+        Middleware(CSRFMiddleware, secret="test-secret", **csrf_kwargs),
+        Middleware(AuthenticationMiddleware, backend=HybridAuthBackend()),
+        Middleware(
+            SessionMiddleware,
+            secret_key=ROMM_AUTH_SECRET_KEY,
+            session_cookie="romm_session",
+            same_site="strict",
+            https_only=False,
+            jwt_alg=ALGORITHM,
+        ),
+    ]
+    return Starlette(routes=routes, middleware=middleware)
+
+
+class TestCSRFMiddleware:
+    def test_csrf_cookie_set_on_first_get(self) -> None:
+        """A GET request should set the CSRF cookie if none exists."""
+        app = create_test_app()
+        client = TestClient(app)
+
+        response = client.get("/get")
+        assert response.status_code == 200
+        assert "csrftoken" in response.cookies
+
+    def test_post_with_valid_token_succeeds(self) -> None:
+        """POST with correct CSRF header should pass."""
+        app = create_test_app()
+        client = TestClient(app)
+
+        # Obtain cookie
+        resp = client.get("/get")
+        cookie = resp.cookies["csrftoken"]
+
+        # Post with token
+        resp = client.post("/post", headers={"x-csrftoken": cookie})
+        assert resp.status_code == 200
+        assert resp.json()["status"] == "success"
+
+    def test_post_without_cookie_fails(self) -> None:
+        """POST without CSRF cookie should fail."""
+        app = create_test_app()
+        client = TestClient(app)
+
+        resp = client.post("/post")
+        assert resp.status_code == 403
+        assert "CSRF token verification failed" in resp.text
+
+    def test_post_without_header_fails(self) -> None:
+        """POST without CSRF header should fail."""
+        app = create_test_app()
+        client = TestClient(app)
+
+        # Obtain cookie but don't send header
+        client.get("/get")
+        resp = client.post("/post")
+        assert resp.status_code == 403
+
+    def test_post_with_bad_signature_fails(self) -> None:
+        """POST with tampered token should fail."""
+        app = create_test_app()
+        client = TestClient(app)
+
+        client.get("/get")
+        bad_token = "tampered-token"
+        resp = client.post("/post", headers={"x-csrftoken": bad_token})
+        assert resp.status_code == 403
+
+    def test_safe_methods_bypass_csrf(self) -> None:
+        """GET/HEAD/OPTIONS/TRACE should never require CSRF."""
+        app = create_test_app()
+        client = TestClient(app)
+
+        for method in ("GET", "HEAD", "OPTIONS", "TRACE"):
+            resp = client.request(method, "/post")
+            assert resp.status_code == 200
+
+    def test_custom_header_name(self) -> None:
+        """Middleware should read the token from the configured header."""
+        header_name = "x-xsrf-token"
+        app = create_test_app(header_name=header_name)
+        client = TestClient(app)
+
+        cookie_resp = client.get("/get")
+        token = cookie_resp.cookies["csrftoken"]
+
+        # Send with custom header
+        resp = client.post("/echo", headers={header_name: token})
+        assert resp.status_code == 200
+        assert resp.json()["token"] == token
+
+    def test_custom_cookie_name(self) -> None:
+        """Middleware should use the configured cookie name."""
+        cookie_name = "my_token"
+        app = create_test_app(cookie_name=cookie_name)
+        client = TestClient(app)
+
+        resp = client.get("/get")
+        assert cookie_name in resp.cookies
+
+    def test_cookie_attributes(self) -> None:
+        """Verify Secure, HttpOnly, SameSite, Path, Domain attributes."""
+        app = create_test_app(
+            cookie_secure=True,
+            cookie_httponly=True,
+            cookie_samesite="strict",
+            cookie_path="/app",
+            cookie_domain=".example.com",
+        )
+        client = TestClient(app)
+
+        resp = client.get("/get")
+        set_cookie = resp.headers["set-cookie"]
+        assert "secure" in set_cookie
+        assert "httponly" in set_cookie
+        assert "samesite=strict" in set_cookie
+        assert "path=/app" in set_cookie
+        assert "domain=.example.com" in set_cookie
+
+    def test_exempt_urls(self) -> None:
+        """POST to exempt URLs should not require CSRF."""
+        app = create_test_app(exempt_urls=[re.compile(r"^/post$")])
+        client = TestClient(app)
+
+        # No cookie/header needed
+        resp = client.post("/post")
+        assert resp.status_code == 200
+
+    def test_required_urls(self) -> None:
+        """POST to required URLs should always require CSRF even for safe methods."""
+        app = create_test_app(required_urls=[re.compile(r"^/get$")], safe_methods=set())
+        client = TestClient(app)
+
+        # GET now requires token
+        resp = client.get("/get")
+        assert resp.status_code == 403
+
+    def test_sensitive_cookies(self) -> None:
+        """If no sensitive cookies exist, CSRF is not enforced."""
+        app = create_test_app(sensitive_cookies={"session"})
+        client = TestClient(app)
+
+        # No sensitive cookie → POST allowed
+        resp = client.post("/post")
+        assert resp.status_code == 200
+
+        # Add sensitive cookie → POST blocked
+        client.cookies.set("session", "abc123")
+        resp = client.post("/post")
+        assert resp.status_code == 403
+
+    # Bypass rules                                                       #
+    def test_bearer_auth_bypass(self) -> None:
+        """Requests with Bearer/Basic Authorization header bypass CSRF."""
+        app = create_test_app()
+        client = TestClient(app)
+
+        resp = client.post("/post", headers={"Authorization": "Bearer token"})
+        assert resp.status_code == 200
+
+    def test_non_http_scope_bypass(self) -> None:
+        """WebSocket (or other non-HTTP) scopes should pass through."""
+        # Manual ASGI call; TestClient doesn't expose WebSocket easily
+        scope = {"type": "websocket", "path": "/ws", "headers": []}
+        receive = lambda: {}  # noqa: E731
+        send = lambda msg: None  # noqa: E731
+
+        async def dummy_app(scope, receive, send):
+            await send({"type": "websocket.accept"})
+
+        middleware = CSRFMiddleware(dummy_app, secret="test")
+        import asyncio
+
+        asyncio.run(middleware(scope, receive, send))  # should not raise
+
+    def test_token_generation_and_validation(self) -> None:
+        """Ensure tokens are signed and validated correctly."""
+        app = create_test_app()
+        client = TestClient(app)
+
+        # Extract cookie
+        resp = client.get("/get")
+        cookie = resp.cookies["csrftoken"]
+
+        # Verify signature
+        serializer = URLSafeSerializer("test-secret", "csrftoken")
+        payload = serializer.loads(cookie)
+        assert "token" in payload
+        assert "user_id" in payload
+
+        # Send same token back
+        resp = client.post("/echo", headers={"x-csrftoken": cookie})
+        assert resp.status_code == 200
+        assert resp.json()["token"] == cookie
+
+    def test_user_id_mismatch_fails(self) -> None:
+        """Tokens issued for one user must not validate for another."""
+        # We simulate two users by calling _generate_csrf_token with different IDs
+        mw = CSRFMiddleware(app=lambda s, r, se: None, secret="test")
+        user1_token = mw._generate_csrf_token(user_id=1)
+        mw._generate_csrf_token(user_id=2)
+
+        # user1_token should not validate for user_id=2
+        assert not mw._csrf_tokens_match(user1_token, user1_token, user_id=2)
+
+    def test_bad_signature_returns_false(self) -> None:
+        """_csrf_tokens_match should return False on BadSignature."""
+        mw = CSRFMiddleware(app=lambda s, r, se: None, secret="test")
+        ok = mw._csrf_tokens_match("bad-token", "bad-token", user_id=None)
+        assert ok is False
diff --git a/backend/tests/handler/auth/test_session_middleware.py b/backend/tests/handler/auth/test_session_middleware.py
new file mode 100644
index 000000000..38f99584a
--- /dev/null
+++ b/backend/tests/handler/auth/test_session_middleware.py
@@ -0,0 +1,366 @@
+"""
+Test suite for SessionMiddleware using JWT-based session management.
+"""
+
+import time
+from typing import Any, Dict
+
+from joserfc import jwt
+from joserfc.jwk import OctKey
+from starlette.applications import Starlette
+from starlette.middleware import Middleware
+from starlette.requests import Request
+from starlette.responses import JSONResponse, PlainTextResponse
+from starlette.routing import Route
+from starlette.testclient import TestClient
+
+from handler.auth.middleware.session_middleware import SessionMiddleware
+
+
+def create_test_app(**middleware_kwargs) -> Starlette:
+    def get_session_data(request: Request) -> Dict[str, Any]:
+        """Extract session data from request"""
+        return dict(request.session)
+
+    def set_session_data(request: Request, data: Dict[str, Any]) -> None:
+        """Set session data"""
+        request.session.update(data)
+
+    def clear_session(request: Request) -> None:
+        """Clear session data"""
+        request.session.clear()
+
+    # Define test app routes
+    async def homepage(request: Request) -> PlainTextResponse:
+        """Basic route that sets default session data."""
+        request.session.setdefault("visited", 0)
+        request.session["visited"] += 1
+        return PlainTextResponse("OK")
+
+    async def set_session(request: Request) -> JSONResponse:
+        """Set specific session data."""
+        data = await request.json()
+        request.session.update(data)
+        return JSONResponse({"session": dict(request.session)})
+
+    async def get_session(request: Request) -> JSONResponse:
+        """Get current session data."""
+        return JSONResponse({"session": dict(request.session)})
+
+    async def clear_session_route(request: Request) -> PlainTextResponse:
+        """Clear the session."""
+        request.session.clear()
+        return PlainTextResponse("Session cleared")
+
+    async def modify_session(request: Request) -> JSONResponse:
+        """Modify session with provided data."""
+        data = await request.json()
+        for key, value in data.items():
+            if value is None:
+                request.session.pop(key, None)
+            else:
+                request.session[key] = value
+        return JSONResponse({"session": dict(request.session)})
+
+    """Create a test app with SessionMiddleware."""
+    routes = [
+        Route("/", homepage),
+        Route("/set", set_session, methods=["POST"]),
+        Route("/get", get_session),
+        Route("/clear", clear_session_route),
+        Route("/modify", modify_session, methods=["POST"]),
+    ]
+    kwargs = {"secret_key": "test-secret-key", **middleware_kwargs}
+    middleware = [Middleware(SessionMiddleware, **kwargs)]
+    return Starlette(routes=routes, middleware=middleware)
+
+
+class TestSessionMiddleware:
+    def test_session_creation(self) -> None:
+        """Test that a session cookie is set on the first request."""
+        app = create_test_app()
+        client = TestClient(app)
+
+        response = client.get("/")
+        assert response.status_code == 200
+        assert "session" in response.cookies
+        assert response.text == "OK"
+
+    def test_session_reading(self) -> None:
+        """Test that session data can be read from the cookie on subsequent requests."""
+        app = create_test_app()
+        client = TestClient(app)
+
+        # First request sets session
+        response = client.get("/")
+        assert response.status_code == 200
+
+        # Second request should read the session
+        response = client.get("/get")
+        assert response.status_code == 200
+        data = response.json()
+        assert "visited" in data["session"]
+        assert data["session"]["visited"] == 1
+
+    def test_session_modification(self) -> None:
+        """Test that session data can be modified and persisted across requests."""
+        app = create_test_app()
+        client = TestClient(app)
+
+        response = client.post("/set", json={"user": "test_user", "role": "admin"})
+        assert response.status_code == 200
+        assert response.json()["session"]["user"] == "test_user"
+
+        response = client.get("/get")
+        assert response.status_code == 200
+        data = response.json()
+        assert data["session"]["user"] == "test_user"
+        assert data["session"]["role"] == "admin"
+
+    def test_session_clearing(self) -> None:
+        """Test that clearing the session removes the cookie."""
+        app = create_test_app()
+        client = TestClient(app)
+
+        response = client.post("/set", json={"user": "test_user"})
+        assert response.status_code == 200
+
+        # Clear session
+        response = client.get("/clear")
+        assert response.status_code == 200
+
+        # Verify session is cleared
+        response = client.get("/get")
+        assert response.status_code == 200
+        data = response.json()
+        assert data["session"] == {}
+
+    def test_session_max_age(self) -> None:
+        """Test that the Max-Age attribute is set correctly."""
+        max_age = 3600
+        app = create_test_app(max_age=max_age)
+        client = TestClient(app)
+
+        response = client.get("/")
+        assert response.status_code == 200
+
+        set_cookie_header = response.headers.get("set-cookie", "")
+        assert f"Max-Age={max_age}" in set_cookie_header
+
+    def test_session_https_only(self) -> None:
+        """Test that the secure flag is set when https_only is True."""
+        app = create_test_app(https_only=True)
+        client = TestClient(app)
+
+        response = client.get("/")
+        assert response.status_code == 200
+
+        set_cookie_header = response.headers.get("set-cookie", "")
+        assert "secure" in set_cookie_header
+
+    def test_session_same_site(self) -> None:
+        """Test that the samesite attribute is set correctly."""
+        app = create_test_app(same_site="strict")
+        client = TestClient(app)
+
+        response = client.get("/")
+        assert response.status_code == 200
+
+        set_cookie_header = response.headers.get("set-cookie", "")
+        assert "samesite=strict" in set_cookie_header
+
+    def test_session_expiration_past(self) -> None:
+        """Test that an expired session is not loaded and a new one is created."""
+        app = create_test_app()
+        client = TestClient(app)
+
+        # Build a token that expired one hour ago
+        expired = int(time.time()) - 3600
+        payload = {"user": "test_user", "exp": expired}
+        key = OctKey.import_key("test-secret-key")
+        token = jwt.encode({"alg": "HS256"}, payload, key=key)
+
+        response = client.get("/get", cookies={"session": token})
+        assert response.status_code == 200
+        # middleware must reject the expired token → empty session
+        assert response.json()["session"] == {}
+
+    def test_session_not_before_future(self) -> None:
+        """Test that a session with a 'not before' claim in the future is ignored."""
+        app = create_test_app()
+        client = TestClient(app)
+
+        # Build a token that is not valid until tomorrow
+        nbf = int(time.time()) + 86400
+        payload = {"user": "test_user", "nbf": nbf}
+        key = OctKey.import_key("test-secret-key")
+        token = jwt.encode({"alg": "HS256"}, payload, key=key)
+
+        response = client.get("/get", cookies={"session": token})
+        assert response.status_code == 200
+        # middleware must reject the future token → empty session
+        assert response.json()["session"] == {}
+
+    def test_session_bad_signature(self) -> None:
+        """Test that a session with a bad signature is ignored and a new session is created."""
+        app = create_test_app()
+        client = TestClient(app)
+
+        # Create a session
+        response = client.post("/set", json={"user": "test_user"})
+        assert response.status_code == 200
+
+        # Tamper with the cookie (simulate bad signature)
+        tampered_cookie = response.cookies["session"][:-10] + "tampereddata"
+        response = client.get("/get", cookies={"session": tampered_cookie})
+        assert response.status_code == 200
+        data = response.json()
+
+        # Should have a new empty session, not the tampered one
+        assert "user" not in data["session"]
+
+    def test_session_cookie_name(self) -> None:
+        """Test that custom session cookie name works."""
+        custom_cookie_name = "my_session"
+        app = create_test_app(session_cookie=custom_cookie_name)
+        client = TestClient(app)
+
+        response = client.get("/")
+        assert response.status_code == 200
+        assert custom_cookie_name in response.cookies
+        assert "session" not in response.cookies
+
+    def test_session_jwt_algorithm(self) -> None:
+        """Test that custom JWT algorithm works."""
+        app = create_test_app(jwt_alg="HS256")
+        client = TestClient(app)
+
+        response = client.post("/set", json={"user": "test_user"})
+        assert response.status_code == 200
+
+        token = response.cookies["session"]
+        decoded = jwt.decode(
+            token,
+            key=OctKey.import_key("test-secret-key"),
+            algorithms=["HS256"],
+        )
+        assert decoded.header["alg"] == "HS256"
+
+    def test_session_data_modification(self) -> None:
+        """Test that session data can be modified correctly."""
+        app = create_test_app()
+        client = TestClient(app)
+
+        # Set initial data
+        response = client.post("/set", json={"counter": 1, "name": "Alice"})
+        assert response.status_code == 200
+
+        # Modify data
+        response = client.post("/modify", json={"counter": 2, "name": None})
+        assert response.status_code == 200
+        data = response.json()
+        assert data["session"]["counter"] == 2
+        assert "name" not in data["session"]  # Should be removed
+
+        # Verify changes persist
+        response = client.get("/get")
+        assert response.status_code == 200
+        data = response.json()
+        assert data["session"]["counter"] == 2
+        assert "name" not in data["session"]
+
+    def test_session_empty_on_first_visit(self) -> None:
+        """Test that session is empty on first visit."""
+        app = create_test_app()
+        client = TestClient(app)
+
+        response = client.get("/get")
+        assert response.status_code == 200
+        data = response.json()
+        assert data["session"] == {}
+
+    def test_session_visits_counter(self) -> None:
+        """Test that the visits counter increments correctly."""
+        app = create_test_app()
+        client = TestClient(app)
+
+        # First visit
+        response = client.get("/")
+        assert response.status_code == 200
+
+        response = client.get("/get")
+        data = response.json()
+        assert data["session"]["visited"] == 1
+
+        # Second visit
+        response = client.get("/")
+        assert response.status_code == 200
+
+        response = client.get("/get")
+        data = response.json()
+        assert data["session"]["visited"] == 2
+
+    def test_session_with_special_characters(self) -> None:
+        """Test that session data with special characters works correctly."""
+        app = create_test_app()
+        client = TestClient(app)
+
+        special_data = {
+            "emoji": "🚀",
+            "unicode": "你好世界",
+            "special": "test@#$%^&*()",
+            "nested": {"list": [1, 2, 3], "dict": {"a": 1}},
+        }
+
+        response = client.post("/set", json=special_data)
+        assert response.status_code == 200
+
+        response = client.get("/get")
+        assert response.status_code == 200
+
+        data = response.json()
+        assert data["session"]["emoji"] == special_data["emoji"]
+        assert data["session"]["unicode"] == special_data["unicode"]
+        assert data["session"]["special"] == special_data["special"]
+        assert data["session"]["nested"] == special_data["nested"]
+
+
+def test_full_session_lifecycle():
+    """Test the complete lifecycle of a session."""
+    app = create_test_app(max_age=3600)
+    client = TestClient(app)
+
+    # Start with no session
+    response = client.get("/get")
+    assert response.status_code == 200
+    assert response.json()["session"] == {}
+
+    # Create a session
+    response = client.post("/set", json={"user": "test_user", "role": "user"})
+    assert response.status_code == 200
+
+    # Verify session persists
+    response = client.get("/get")
+    assert response.status_code == 200
+    data = response.json()
+    assert data["session"]["user"] == "test_user"
+    assert data["session"]["role"] == "user"
+
+    # Modify session
+    response = client.post("/modify", json={"role": "admin"})
+    assert response.status_code == 200
+
+    # Verify modification
+    response = client.get("/get")
+    assert response.status_code == 200
+    data = response.json()
+    assert data["session"]["role"] == "admin"
+
+    # Clear session
+    response = client.get("/clear")
+    assert response.status_code == 200
+
+    # Verify session is cleared
+    response = client.get("/get")
+    assert response.status_code == 200
+    assert response.json()["session"] == {}
diff --git a/pyproject.toml b/pyproject.toml
index c66d66f1c..81cc5950a 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -24,7 +24,7 @@ dependencies = [
   "fastapi[standard-no-fastapi-cloud-cli] ~= 0.121.1",
   "gunicorn ~= 23.0",
   "httpx ~= 0.27",
-  "itsdangerous>=2.2.0",
+  "itsdangerous ~= 2.2",
   "joserfc ~= 1.3.4",
   "opentelemetry-distro ~= 0.56",
   "opentelemetry-exporter-otlp ~= 1.36",
diff --git a/uv.lock b/uv.lock
index 4083570ab..fb5f93452 100644
--- a/uv.lock
+++ b/uv.lock
@@ -1982,7 +1982,7 @@ requires-dist = [
     { name = "httpx", specifier = "~=0.27" },
     { name = "ipdb", marker = "extra == 'dev'", specifier = "~=0.13" },
     { name = "ipykernel", marker = "extra == 'dev'", specifier = "~=6.29" },
-    { name = "itsdangerous", specifier = ">=2.2.0" },
+    { name = "itsdangerous", specifier = "~=2.2" },
     { name = "joserfc", specifier = "~=1.3.4" },
     { name = "memray", marker = "extra == 'dev'", specifier = "~=1.15" },
     { name = "mypy", marker = "extra == 'dev'", specifier = "~=1.13" },