diff --git a/src/api_server/swagger/firecracker.yaml b/src/api_server/swagger/firecracker.yaml
index 5a4977ef294..faffaa2eeb8 100644
--- a/src/api_server/swagger/firecracker.yaml
+++ b/src/api_server/swagger/firecracker.yaml
@@ -905,7 +905,10 @@ definitions:
           This parameter has been deprecated since v1.6.0.
           Use parameters in `file` instead.
         $ref: "#/definitions/RateLimiter"
-
+      vhost_user:
+        description:
+          Configuration for the vhost-user-backed device.
+        $ref: "#/definitions/VhostUserConfig"
   Error:
     type: object
     properties:
@@ -1302,6 +1305,15 @@ definitions:
         description: The total number of tokens this bucket can hold.
         minimum: 0
 
+  VhostUserConfig:
+    type: object
+    required:
+     - socket
+    properties:
+      socket:
+        type: string
+        description: Socket path for vhost-user backend.
+
   Vm:
     type: object
     description:
diff --git a/tests/framework/vm_config.json b/tests/framework/vm_config.json
index 2244c7227f1..9c83ff218c4 100644
--- a/tests/framework/vm_config.json
+++ b/tests/framework/vm_config.json
@@ -19,7 +19,8 @@
         "is_read_only": false,
         "io_engine": "Sync",
         "rate_limiter": null
-      }
+      },
+      "vhost_user": null
     }
   ],
   "machine-config": {
diff --git a/tests/framework/vm_config_cpu_template_C3.json b/tests/framework/vm_config_cpu_template_C3.json
index 34163aa5377..fd18de4c5c2 100644
--- a/tests/framework/vm_config_cpu_template_C3.json
+++ b/tests/framework/vm_config_cpu_template_C3.json
@@ -12,7 +12,8 @@
       "file": {
         "path_on_host": "bionic.rootfs.ext4",
         "is_read_only": false
-      }
+      },
+      "vhost_user": null
     }
   ],
   "machine-config": {
diff --git a/tests/framework/vm_config_missing_mem_size_mib.json b/tests/framework/vm_config_missing_mem_size_mib.json
index 56bb358c299..edb1cf539e2 100644
--- a/tests/framework/vm_config_missing_mem_size_mib.json
+++ b/tests/framework/vm_config_missing_mem_size_mib.json
@@ -12,7 +12,8 @@
       "file": {
         "path_on_host": "bionic.rootfs.ext4",
         "is_read_only": false
-      }
+      },
+      "vhost_user": null
     }
   ],
   "machine-config": {
diff --git a/tests/framework/vm_config_missing_vcpu_count.json b/tests/framework/vm_config_missing_vcpu_count.json
index f60b80b101e..d82136dc6ff 100644
--- a/tests/framework/vm_config_missing_vcpu_count.json
+++ b/tests/framework/vm_config_missing_vcpu_count.json
@@ -12,7 +12,8 @@
       "file": {
         "path_on_host": "bionic.rootfs.ext4",
         "is_read_only": false
-      }
+      },
+      "vhost_user": null
     }
   ],
   "machine-config": {
diff --git a/tests/framework/vm_config_smt_true.json b/tests/framework/vm_config_smt_true.json
index 7a22425c26a..800b6e0f4ee 100644
--- a/tests/framework/vm_config_smt_true.json
+++ b/tests/framework/vm_config_smt_true.json
@@ -12,7 +12,8 @@
       "file": {
         "path_on_host": "bionic.rootfs.ext4",
         "is_read_only": false
-      }
+      },
+      "vhost_user": null
     }
   ],
   "machine-config": {
diff --git a/tests/framework/vm_config_with_mmdsv1.json b/tests/framework/vm_config_with_mmdsv1.json
index 1112b111baa..0ca76dd2af7 100644
--- a/tests/framework/vm_config_with_mmdsv1.json
+++ b/tests/framework/vm_config_with_mmdsv1.json
@@ -19,7 +19,8 @@
         "is_read_only": false,
         "io_engine": "Sync",
         "rate_limiter": null
-      }
+      },
+      "vhost_user": null
     }
   ],
   "machine-config": {
diff --git a/tests/framework/vm_config_with_mmdsv2.json b/tests/framework/vm_config_with_mmdsv2.json
index 8c6a49ff3b7..15c14e86061 100644
--- a/tests/framework/vm_config_with_mmdsv2.json
+++ b/tests/framework/vm_config_with_mmdsv2.json
@@ -19,7 +19,8 @@
         "is_read_only": false,
         "io_engine": "Sync",
         "rate_limiter": null
-      }
+      },
+      "vhost_user": null
     }
   ],
   "machine-config": {
diff --git a/tests/integration_tests/functional/test_api.py b/tests/integration_tests/functional/test_api.py
index fb47c22abde..28bb0169fac 100644
--- a/tests/integration_tests/functional/test_api.py
+++ b/tests/integration_tests/functional/test_api.py
@@ -849,6 +849,7 @@ def _drive_patch(test_microvm):
                 "rate_limiter": None,
                 "io_engine": "Sync",
             },
+            "vhost_user": None,
         },
         {
             "drive_id": "scratch",
@@ -875,6 +876,7 @@ def _drive_patch(test_microvm):
                 },
                 "io_engine": "Async" if is_io_uring_supported() else "Sync",
             },
+            "vhost_user": None,
         },
     ]
 
@@ -1081,6 +1083,7 @@ def test_get_full_config_after_restoring_snapshot(microvm_factory, uvm_nano):
                 "rate_limiter": None,
                 "io_engine": "Sync",
             },
+            "vhost_user": None,
         }
     ]
 
@@ -1196,6 +1199,7 @@ def test_get_full_config(test_microvm_with_api):
                 "rate_limiter": None,
                 "io_engine": "Sync",
             },
+            "vhost_user": None,
         }
     ]