fix: Endpoint /sessions/me bypasses _Session protectedFields ([GHSA-g4v2-qx3q-4p64](GHSA-g4v2-qx3q-4p64)) (#10406)

Author: mtrezza

spec/vulnerabilities.spec.js

@@ -5685,4 +5685,65 @@ describe('Vulnerabilities', () => {
       expect(response.status).toBe(403);
     });
   });
+
+  describe('(GHSA-g4v2-qx3q-4p64) /sessions/me bypasses _Session protectedFields', () => {
+    const headers = {
+      'X-Parse-Application-Id': 'test',
+      'X-Parse-REST-API-Key': 'rest',
+      'Content-Type': 'application/json',
+    };
+
+    it('should not return protected fields on GET /sessions/me', async () => {
+      await reconfigureServer({
+        protectedFields: {
+          _Session: { '*': ['createdWith'] },
+        },
+      });
+      const user = new Parse.User();
+      user.setUsername('session-pf-user');
+      user.setPassword('password123');
+      user.set('email', 'session-pf@example.com');
+      await user.signUp();
+      const sessionToken = user.getSessionToken();
+
+      // Normal GET /sessions should strip createdWith
+      const sessionsResponse = await request({
+        method: 'GET',
+        url: 'http://localhost:8378/1/sessions',
+        headers: { ...headers, 'X-Parse-Session-Token': sessionToken },
+      });
+      expect(sessionsResponse.data.results[0].createdWith).toBeUndefined();
+
+      // GET /sessions/me should also strip createdWith
+      const meResponse = await request({
+        method: 'GET',
+        url: 'http://localhost:8378/1/sessions/me',
+        headers: { ...headers, 'X-Parse-Session-Token': sessionToken },
+      });
+      expect(meResponse.data.createdWith).toBeUndefined();
+    });
+
+    it('should return non-protected fields on GET /sessions/me', async () => {
+      await reconfigureServer({
+        protectedFields: {
+          _Session: { '*': ['createdWith'] },
+        },
+      });
+      const user = new Parse.User();
+      user.setUsername('session-pf-user2');
+      user.setPassword('password123');
+      user.set('email', 'session-pf2@example.com');
+      await user.signUp();
+      const sessionToken = user.getSessionToken();
+
+      const meResponse = await request({
+        method: 'GET',
+        url: 'http://localhost:8378/1/sessions/me',
+        headers: { ...headers, 'X-Parse-Session-Token': sessionToken },
+      });
+      expect(meResponse.data.sessionToken).toBe(sessionToken);
+      expect(meResponse.data.objectId).toBeDefined();
+      expect(meResponse.data.user).toBeDefined();
+    });
+  });
 });

src/Routers/SessionsRouter.js

@@ -9,29 +9,53 @@ export class SessionsRouter extends ClassesRouter {
     return '_Session';
   }
 
-  handleMe(req) {
-    // TODO: Verify correct behavior
+  async handleMe(req) {
     if (!req.info || !req.info.sessionToken) {
       throw new Parse.Error(Parse.Error.INVALID_SESSION_TOKEN, 'Session token required.');
     }
-    return rest
-      .find(
-        req.config,
-        Auth.master(req.config),
-        '_Session',
-        { sessionToken: req.info.sessionToken },
-        undefined,
-        req.info.clientSDK,
-        req.info.context
-      )
-      .then(response => {
-        if (!response.results || response.results.length == 0) {
-          throw new Parse.Error(Parse.Error.INVALID_SESSION_TOKEN, 'Session token not found.');
-        }
-        return {
-          response: response.results[0],
-        };
-      });
+    const sessionToken = req.info.sessionToken;
+    // Query with master key to validate the session token and get the session objectId
+    const sessionResponse = await rest.find(
+      req.config,
+      Auth.master(req.config),
+      '_Session',
+      { sessionToken },
+      {},
+      req.info.clientSDK,
+      req.info.context
+    );
+    if (
+      !sessionResponse.results ||
+      sessionResponse.results.length == 0 ||
+      !sessionResponse.results[0].user
+    ) {
+      throw new Parse.Error(Parse.Error.INVALID_SESSION_TOKEN, 'Session token not found.');
+    }
+    const sessionObjectId = sessionResponse.results[0].objectId;
+    const userId = sessionResponse.results[0].user.objectId;
+    // Re-fetch the session with the caller's auth context so that
+    // protectedFields and CLP apply correctly
+    const userAuth = new Auth.Auth({
+      config: req.config,
+      isMaster: false,
+      user: Parse.Object.fromJSON({ className: '_User', objectId: userId }),
+      installationId: req.info.installationId,
+    });
+    const response = await rest.get(
+      req.config,
+      userAuth,
+      '_Session',
+      sessionObjectId,
+      {},
+      req.info.clientSDK,
+      req.info.context
+    );
+    if (!response.results || response.results.length == 0) {
+      throw new Parse.Error(Parse.Error.INVALID_SESSION_TOKEN, 'Session token not found.');
+    }
+    return {
+      response: response.results[0],
+    };
   }
 
   handleUpdateToRevocableSession(req) {