diff --git a/src/adapters/routes.ts b/src/adapters/routes.ts
index 34d9245..75a1235 100644
--- a/src/adapters/routes.ts
+++ b/src/adapters/routes.ts
@@ -1,5 +1,6 @@
 import { Router } from '@well-known-components/http-server'
 import * as authorizationMiddleware from 'decentraland-crypto-middleware'
+import { withSignerValidation } from '../middlewares/withSignerValidation'
 import { GlobalContext } from '../types'
 import { createBidsHandler } from './handlers/bids'
 import { createOrdersHandler } from './handlers/orders'
@@ -39,6 +40,7 @@ export async function setupRoutes(globalContext: GlobalContext) {
       optional: true,
       expiration: FIVE_MINUTES,
     }),
+    withSignerValidation,
     createNFTsHandler(components)
   )
   router.get(
@@ -47,6 +49,7 @@ export async function setupRoutes(globalContext: GlobalContext) {
       optional: true,
       expiration: FIVE_MINUTES,
     }),
+    withSignerValidation,
     createItemsHandler(components)
   )
   router.get('/contracts', createContractsHandler(components))
@@ -71,6 +74,7 @@ export async function setupRoutes(globalContext: GlobalContext) {
       optional: true,
       expiration: FIVE_MINUTES,
     }),
+    withSignerValidation,
     createCatalogHandler(components)
   )
 
diff --git a/src/middlewares/withSignerValidation.ts b/src/middlewares/withSignerValidation.ts
new file mode 100644
index 0000000..8bf2b61
--- /dev/null
+++ b/src/middlewares/withSignerValidation.ts
@@ -0,0 +1,20 @@
+import { IHttpServerComponent } from '@well-known-components/interfaces'
+
+export async function withSignerValidation(
+  ctx: IHttpServerComponent.DefaultContext<any>,
+  next: () => Promise<IHttpServerComponent.IResponse>
+): Promise<IHttpServerComponent.IResponse> {
+  if (
+    ctx.verification &&
+    ctx.verification.authMetadata &&
+    typeof ctx.verification.authMetadata === 'object' &&
+    ctx.verification.authMetadata.signer === 'decentraland-kernel-scene'
+  ) {
+    return {
+      status: 400,
+      body: 'Invalid signer',
+    }
+  }
+
+  return await next()
+}
diff --git a/src/tests/middlewares/withSignerValidation.spec.ts b/src/tests/middlewares/withSignerValidation.spec.ts
new file mode 100644
index 0000000..fd32e36
--- /dev/null
+++ b/src/tests/middlewares/withSignerValidation.spec.ts
@@ -0,0 +1,64 @@
+import { IHttpServerComponent } from "@well-known-components/interfaces"
+import { withSignerValidation } from "../../middlewares/withSignerValidation"
+
+let ctx: IHttpServerComponent.DefaultContext<any>
+
+describe("withSignerValidation", () => {
+  describe("when signer is decentraland-kernel-scene", () => {
+    beforeEach(() => {
+      ctx = {
+        verification: {
+          authMetadata: {
+            signer: "decentraland-kernel-scene",
+          },
+        },
+      }
+    })
+
+    it('should return 400 status and "Invalid signer" body', async () => {
+      const next = jest.fn()
+      const result = await withSignerValidation(ctx, next)
+      expect(result).toEqual({
+        status: 400,
+        body: "Invalid signer",
+      })
+      expect(next).not.toHaveBeenCalled()
+    })
+  })
+
+  describe("when signer is not defined", () => {
+    beforeEach(() => {
+      ctx = {
+        verification: {
+          authMetadata: {},
+        },
+      }
+    })
+
+    it("should call next() and return its result", async () => {
+      const nextResult = { status: 200, body: "Success" }
+      const next = jest.fn().mockResolvedValue(nextResult)
+      const result = await withSignerValidation(ctx, next)
+      expect(result).toEqual(nextResult)
+      expect(next).toHaveBeenCalled()
+    })
+  })
+
+  describe('when signer is not "decentraland-kernel-scene"', () => {
+    beforeEach(() => {
+      ctx = {
+        verification: {
+          authMetadata: { signer: "other-signer" },
+        },
+      }
+    })
+
+    it("should call next() and return its result", async () => {
+      const nextResult = { status: 200, body: "Success" }
+      const next = jest.fn().mockResolvedValue(nextResult)
+      const result = await withSignerValidation(ctx, next)
+      expect(result).toEqual(nextResult)
+      expect(next).toHaveBeenCalled()
+    })
+  })
+})