diff --git a/src/wp-includes/rest-api/endpoints/class-wp-rest-block-renderer-controller.php b/src/wp-includes/rest-api/endpoints/class-wp-rest-block-renderer-controller.php
index 3bdcae5435..3388078d05 100644
--- a/src/wp-includes/rest-api/endpoints/class-wp-rest-block-renderer-controller.php
+++ b/src/wp-includes/rest-api/endpoints/class-wp-rest-block-renderer-controller.php
@@ -34,47 +34,52 @@ class WP_REST_Block_Renderer_Controller extends WP_REST_Controller {
 	 * @see register_rest_route()
 	 */
 	public function register_routes() {
-		$block_types = WP_Block_Type_Registry::get_instance()->get_all_registered();
-
-		foreach ( $block_types as $block_type ) {
-			if ( ! $block_type->is_dynamic() ) {
-				continue;
-			}
-
-			register_rest_route(
-				$this->namespace,
-				'/' . $this->rest_base . '/(?P<name>' . $block_type->name . ')',
+		register_rest_route(
+			$this->namespace,
+			'/' . $this->rest_base . '/(?P<name>[a-z0-9-]+/[a-z0-9-]+)',
+			array(
+				'args'   => array(
+					'name' => array(
+						'description' => __( 'Unique registered name for the block.' ),
+						'type'        => 'string',
+					),
+				),
 				array(
-					'args'   => array(
-						'name' => array(
-							'description' => __( 'Unique registered name for the block.' ),
-							'type'        => 'string',
+					'methods'             => array( WP_REST_Server::READABLE, WP_REST_Server::CREATABLE ),
+					'callback'            => array( $this, 'get_item' ),
+					'permission_callback' => array( $this, 'get_item_permissions_check' ),
+					'args'                => array(
+						'context'    => $this->get_context_param( array( 'default' => 'view' ) ),
+						'attributes' => array(
+							'description'       => __( 'Attributes for the block' ),
+							'type'              => 'object',
+							'default'           => array(),
+							'validate_callback' => static function ( $value, $request ) {
+								$block = WP_Block_Type_Registry::get_instance()->get_registered( $request['name'] );
+
+								if ( ! $block ) {
+									// This will get rejected in ::get_item().
+									return true;
+								}
+
+								$schema = array(
+									'type'                 => 'object',
+									'properties'           => $block->get_attributes(),
+									'additionalProperties' => false,
+								);
+
+								return rest_validate_value_from_schema( $value, $schema );
+							},
+						),
+						'post_id'    => array(
+							'description' => __( 'ID of the post context.' ),
+							'type'        => 'integer',
 						),
 					),
-					array(
-						'methods'             => array( WP_REST_Server::READABLE, WP_REST_Server::CREATABLE ),
-						'callback'            => array( $this, 'get_item' ),
-						'permission_callback' => array( $this, 'get_item_permissions_check' ),
-						'args'                => array(
-							'context'    => $this->get_context_param( array( 'default' => 'view' ) ),
-							'attributes' => array(
-								/* translators: %s: The name of the block. */
-								'description'          => sprintf( __( 'Attributes for %s block' ), $block_type->name ),
-								'type'                 => 'object',
-								'additionalProperties' => false,
-								'properties'           => $block_type->get_attributes(),
-								'default'              => array(),
-							),
-							'post_id'    => array(
-								'description' => __( 'ID of the post context.' ),
-								'type'        => 'integer',
-							),
-						),
-					),
-					'schema' => array( $this, 'get_public_item_schema' ),
-				)
-			);
-		}
+				),
+				'schema' => array( $this, 'get_public_item_schema' ),
+			)
+		);
 	}
 
 	/**
@@ -136,9 +141,11 @@ class WP_REST_Block_Renderer_Controller extends WP_REST_Controller {
 			// Set up postdata since this will be needed if post_id was set.
 			setup_postdata( $post );
 		}
-		$registry = WP_Block_Type_Registry::get_instance();
 
-		if ( null === $registry->get_registered( $request['name'] ) ) {
+		$registry   = WP_Block_Type_Registry::get_instance();
+		$registered = $registry->get_registered( $request['name'] );
+
+		if ( null === $registered || ! $registered->is_dynamic() ) {
 			return new WP_Error(
 				'block_invalid',
 				__( 'Invalid block.' ),
diff --git a/tests/phpunit/tests/rest-api/rest-block-renderer-controller.php b/tests/phpunit/tests/rest-api/rest-block-renderer-controller.php
index 88b1b69bde..439f59b92c 100644
--- a/tests/phpunit/tests/rest-api/rest-block-renderer-controller.php
+++ b/tests/phpunit/tests/rest-api/rest-block-renderer-controller.php
@@ -46,6 +46,15 @@ class REST_Block_Renderer_Controller_Test extends WP_Test_REST_Controller_Testca
 	 */
 	protected static $context_block_name = 'core/context-test-block';
 
+	/**
+	 * Non dynamic block name.
+	 *
+	 * @since 5.5.0
+	 *
+	 * @var string
+	 */
+	protected static $non_dynamic_block_name = 'core/non-dynamic';
+
 	/**
 	 * Test API user's ID.
 	 *
@@ -117,6 +126,7 @@ class REST_Block_Renderer_Controller_Test extends WP_Test_REST_Controller_Testca
 	public function setUp() {
 		$this->register_test_block();
 		$this->register_post_context_test_block();
+		$this->register_non_dynamic_block();
 		parent::setUp();
 	}
 
@@ -128,6 +138,7 @@ class REST_Block_Renderer_Controller_Test extends WP_Test_REST_Controller_Testca
 	public function tearDown() {
 		WP_Block_Type_Registry::get_instance()->unregister( self::$block_name );
 		WP_Block_Type_Registry::get_instance()->unregister( self::$context_block_name );
+		WP_Block_Type_Registry::get_instance()->unregister( self::$non_dynamic_block_name );
 		parent::tearDown();
 	}
 
@@ -175,6 +186,15 @@ class REST_Block_Renderer_Controller_Test extends WP_Test_REST_Controller_Testca
 		);
 	}
 
+	/**
+	 * Registers the non-dynamic block name.
+	 *
+	 * @since 5.5.0
+	 */
+	protected function register_non_dynamic_block() {
+		register_block_type( self::$non_dynamic_block_name );
+	}
+
 	/**
 	 * Test render callback.
 	 *
@@ -210,9 +230,7 @@ class REST_Block_Renderer_Controller_Test extends WP_Test_REST_Controller_Testca
 		$this->assertContains( self::$block_name, $dynamic_block_names );
 
 		$routes = rest_get_server()->get_routes();
-		foreach ( $dynamic_block_names as $dynamic_block_name ) {
-			$this->assertArrayHasKey( self::$rest_api_route . "(?P<name>$dynamic_block_name)", $routes );
-		}
+		$this->assertArrayHasKey( self::$rest_api_route . '(?P<name>[a-z0-9-]+/[a-z0-9-]+)', $routes );
 	}
 
 	/**
@@ -261,7 +279,7 @@ class REST_Block_Renderer_Controller_Test extends WP_Test_REST_Controller_Testca
 		$request->set_param( 'context', 'edit' );
 		$response = rest_get_server()->dispatch( $request );
 
-		$this->assertErrorResponse( 'rest_no_route', $response, 404 );
+		$this->assertErrorResponse( 'block_invalid', $response, 404 );
 	}
 
 	/**
@@ -510,6 +528,19 @@ class REST_Block_Renderer_Controller_Test extends WP_Test_REST_Controller_Testca
 		$this->assertErrorResponse( 'block_cannot_read', $response, 403 );
 	}
 
+	/**
+	 * @ticket 48079
+	 */
+	public function test_get_item_non_dynamic_block() {
+		wp_set_current_user( self::$user_id );
+		$request = new WP_REST_Request( 'GET', self::$rest_api_route . self::$non_dynamic_block_name );
+
+		$request->set_param( 'context', 'edit' );
+		$response = rest_get_server()->dispatch( $request );
+
+		$this->assertErrorResponse( 'block_invalid', $response, 404 );
+	}
+
 	/**
 	 * Get item schema.
 	 *
diff --git a/tests/phpunit/tests/rest-api/rest-schema-setup.php b/tests/phpunit/tests/rest-api/rest-schema-setup.php
index c60170d45a..3561314dbe 100644
--- a/tests/phpunit/tests/rest-api/rest-schema-setup.php
+++ b/tests/phpunit/tests/rest-api/rest-schema-setup.php
@@ -120,17 +120,7 @@ class WP_Test_REST_Schema_Initialization extends WP_Test_REST_TestCase {
 			'/wp/v2/comments',
 			'/wp/v2/comments/(?P<id>[\\d]+)',
 			'/wp/v2/search',
-			'/wp/v2/block-renderer/(?P<name>core/archives)',
-			'/wp/v2/block-renderer/(?P<name>core/block)',
-			'/wp/v2/block-renderer/(?P<name>core/calendar)',
-			'/wp/v2/block-renderer/(?P<name>core/categories)',
-			'/wp/v2/block-renderer/(?P<name>core/latest-comments)',
-			'/wp/v2/block-renderer/(?P<name>core/latest-posts)',
-			'/wp/v2/block-renderer/(?P<name>core/rss)',
-			'/wp/v2/block-renderer/(?P<name>core/search)',
-			'/wp/v2/block-renderer/(?P<name>core/shortcode)',
-			'/wp/v2/block-renderer/(?P<name>core/social-link)',
-			'/wp/v2/block-renderer/(?P<name>core/tag-cloud)',
+			'/wp/v2/block-renderer/(?P<name>[a-z0-9-]+/[a-z0-9-]+)',
 			'/wp/v2/settings',
 			'/wp/v2/themes',
 		);
diff --git a/tests/qunit/fixtures/wp-api-generated.js b/tests/qunit/fixtures/wp-api-generated.js
index 2da6be93b5..280144750d 100644
--- a/tests/qunit/fixtures/wp-api-generated.js
+++ b/tests/qunit/fixtures/wp-api-generated.js
@@ -4394,7 +4394,7 @@ mockedApiResponse.Schema = {
                 "self": "http://example.org/index.php?rest_route=/wp/v2/search"
             }
         },
-        "/wp/v2/block-renderer/(?P<name>core/archives)": {
+        "/wp/v2/block-renderer/(?P<name>[a-z0-9-]+/[a-z0-9-]+)": {
             "namespace": "wp/v2",
             "methods": [
                 "GET",
@@ -4424,427 +4424,7 @@ mockedApiResponse.Schema = {
                         "attributes": {
                             "required": false,
                             "default": [],
-                            "description": "Attributes for core/archives block",
-                            "type": "object"
-                        },
-                        "post_id": {
-                            "required": false,
-                            "description": "ID of the post context.",
-                            "type": "integer"
-                        }
-                    }
-                }
-            ]
-        },
-        "/wp/v2/block-renderer/(?P<name>core/block)": {
-            "namespace": "wp/v2",
-            "methods": [
-                "GET",
-                "POST"
-            ],
-            "endpoints": [
-                {
-                    "methods": [
-                        "GET",
-                        "POST"
-                    ],
-                    "args": {
-                        "name": {
-                            "required": false,
-                            "description": "Unique registered name for the block.",
-                            "type": "string"
-                        },
-                        "context": {
-                            "required": false,
-                            "default": "view",
-                            "enum": [
-                                "edit"
-                            ],
-                            "description": "Scope under which the request is made; determines fields present in response.",
-                            "type": "string"
-                        },
-                        "attributes": {
-                            "required": false,
-                            "default": [],
-                            "description": "Attributes for core/block block",
-                            "type": "object"
-                        },
-                        "post_id": {
-                            "required": false,
-                            "description": "ID of the post context.",
-                            "type": "integer"
-                        }
-                    }
-                }
-            ]
-        },
-        "/wp/v2/block-renderer/(?P<name>core/calendar)": {
-            "namespace": "wp/v2",
-            "methods": [
-                "GET",
-                "POST"
-            ],
-            "endpoints": [
-                {
-                    "methods": [
-                        "GET",
-                        "POST"
-                    ],
-                    "args": {
-                        "name": {
-                            "required": false,
-                            "description": "Unique registered name for the block.",
-                            "type": "string"
-                        },
-                        "context": {
-                            "required": false,
-                            "default": "view",
-                            "enum": [
-                                "edit"
-                            ],
-                            "description": "Scope under which the request is made; determines fields present in response.",
-                            "type": "string"
-                        },
-                        "attributes": {
-                            "required": false,
-                            "default": [],
-                            "description": "Attributes for core/calendar block",
-                            "type": "object"
-                        },
-                        "post_id": {
-                            "required": false,
-                            "description": "ID of the post context.",
-                            "type": "integer"
-                        }
-                    }
-                }
-            ]
-        },
-        "/wp/v2/block-renderer/(?P<name>core/categories)": {
-            "namespace": "wp/v2",
-            "methods": [
-                "GET",
-                "POST"
-            ],
-            "endpoints": [
-                {
-                    "methods": [
-                        "GET",
-                        "POST"
-                    ],
-                    "args": {
-                        "name": {
-                            "required": false,
-                            "description": "Unique registered name for the block.",
-                            "type": "string"
-                        },
-                        "context": {
-                            "required": false,
-                            "default": "view",
-                            "enum": [
-                                "edit"
-                            ],
-                            "description": "Scope under which the request is made; determines fields present in response.",
-                            "type": "string"
-                        },
-                        "attributes": {
-                            "required": false,
-                            "default": [],
-                            "description": "Attributes for core/categories block",
-                            "type": "object"
-                        },
-                        "post_id": {
-                            "required": false,
-                            "description": "ID of the post context.",
-                            "type": "integer"
-                        }
-                    }
-                }
-            ]
-        },
-        "/wp/v2/block-renderer/(?P<name>core/latest-comments)": {
-            "namespace": "wp/v2",
-            "methods": [
-                "GET",
-                "POST"
-            ],
-            "endpoints": [
-                {
-                    "methods": [
-                        "GET",
-                        "POST"
-                    ],
-                    "args": {
-                        "name": {
-                            "required": false,
-                            "description": "Unique registered name for the block.",
-                            "type": "string"
-                        },
-                        "context": {
-                            "required": false,
-                            "default": "view",
-                            "enum": [
-                                "edit"
-                            ],
-                            "description": "Scope under which the request is made; determines fields present in response.",
-                            "type": "string"
-                        },
-                        "attributes": {
-                            "required": false,
-                            "default": [],
-                            "description": "Attributes for core/latest-comments block",
-                            "type": "object"
-                        },
-                        "post_id": {
-                            "required": false,
-                            "description": "ID of the post context.",
-                            "type": "integer"
-                        }
-                    }
-                }
-            ]
-        },
-        "/wp/v2/block-renderer/(?P<name>core/latest-posts)": {
-            "namespace": "wp/v2",
-            "methods": [
-                "GET",
-                "POST"
-            ],
-            "endpoints": [
-                {
-                    "methods": [
-                        "GET",
-                        "POST"
-                    ],
-                    "args": {
-                        "name": {
-                            "required": false,
-                            "description": "Unique registered name for the block.",
-                            "type": "string"
-                        },
-                        "context": {
-                            "required": false,
-                            "default": "view",
-                            "enum": [
-                                "edit"
-                            ],
-                            "description": "Scope under which the request is made; determines fields present in response.",
-                            "type": "string"
-                        },
-                        "attributes": {
-                            "required": false,
-                            "default": [],
-                            "description": "Attributes for core/latest-posts block",
-                            "type": "object"
-                        },
-                        "post_id": {
-                            "required": false,
-                            "description": "ID of the post context.",
-                            "type": "integer"
-                        }
-                    }
-                }
-            ]
-        },
-        "/wp/v2/block-renderer/(?P<name>core/rss)": {
-            "namespace": "wp/v2",
-            "methods": [
-                "GET",
-                "POST"
-            ],
-            "endpoints": [
-                {
-                    "methods": [
-                        "GET",
-                        "POST"
-                    ],
-                    "args": {
-                        "name": {
-                            "required": false,
-                            "description": "Unique registered name for the block.",
-                            "type": "string"
-                        },
-                        "context": {
-                            "required": false,
-                            "default": "view",
-                            "enum": [
-                                "edit"
-                            ],
-                            "description": "Scope under which the request is made; determines fields present in response.",
-                            "type": "string"
-                        },
-                        "attributes": {
-                            "required": false,
-                            "default": [],
-                            "description": "Attributes for core/rss block",
-                            "type": "object"
-                        },
-                        "post_id": {
-                            "required": false,
-                            "description": "ID of the post context.",
-                            "type": "integer"
-                        }
-                    }
-                }
-            ]
-        },
-        "/wp/v2/block-renderer/(?P<name>core/search)": {
-            "namespace": "wp/v2",
-            "methods": [
-                "GET",
-                "POST"
-            ],
-            "endpoints": [
-                {
-                    "methods": [
-                        "GET",
-                        "POST"
-                    ],
-                    "args": {
-                        "name": {
-                            "required": false,
-                            "description": "Unique registered name for the block.",
-                            "type": "string"
-                        },
-                        "context": {
-                            "required": false,
-                            "default": "view",
-                            "enum": [
-                                "edit"
-                            ],
-                            "description": "Scope under which the request is made; determines fields present in response.",
-                            "type": "string"
-                        },
-                        "attributes": {
-                            "required": false,
-                            "default": [],
-                            "description": "Attributes for core/search block",
-                            "type": "object"
-                        },
-                        "post_id": {
-                            "required": false,
-                            "description": "ID of the post context.",
-                            "type": "integer"
-                        }
-                    }
-                }
-            ]
-        },
-        "/wp/v2/block-renderer/(?P<name>core/shortcode)": {
-            "namespace": "wp/v2",
-            "methods": [
-                "GET",
-                "POST"
-            ],
-            "endpoints": [
-                {
-                    "methods": [
-                        "GET",
-                        "POST"
-                    ],
-                    "args": {
-                        "name": {
-                            "required": false,
-                            "description": "Unique registered name for the block.",
-                            "type": "string"
-                        },
-                        "context": {
-                            "required": false,
-                            "default": "view",
-                            "enum": [
-                                "edit"
-                            ],
-                            "description": "Scope under which the request is made; determines fields present in response.",
-                            "type": "string"
-                        },
-                        "attributes": {
-                            "required": false,
-                            "default": [],
-                            "description": "Attributes for core/shortcode block",
-                            "type": "object"
-                        },
-                        "post_id": {
-                            "required": false,
-                            "description": "ID of the post context.",
-                            "type": "integer"
-                        }
-                    }
-                }
-            ]
-        },
-        "/wp/v2/block-renderer/(?P<name>core/social-link)": {
-            "namespace": "wp/v2",
-            "methods": [
-                "GET",
-                "POST"
-            ],
-            "endpoints": [
-                {
-                    "methods": [
-                        "GET",
-                        "POST"
-                    ],
-                    "args": {
-                        "name": {
-                            "required": false,
-                            "description": "Unique registered name for the block.",
-                            "type": "string"
-                        },
-                        "context": {
-                            "required": false,
-                            "default": "view",
-                            "enum": [
-                                "edit"
-                            ],
-                            "description": "Scope under which the request is made; determines fields present in response.",
-                            "type": "string"
-                        },
-                        "attributes": {
-                            "required": false,
-                            "default": [],
-                            "description": "Attributes for core/social-link block",
-                            "type": "object"
-                        },
-                        "post_id": {
-                            "required": false,
-                            "description": "ID of the post context.",
-                            "type": "integer"
-                        }
-                    }
-                }
-            ]
-        },
-        "/wp/v2/block-renderer/(?P<name>core/tag-cloud)": {
-            "namespace": "wp/v2",
-            "methods": [
-                "GET",
-                "POST"
-            ],
-            "endpoints": [
-                {
-                    "methods": [
-                        "GET",
-                        "POST"
-                    ],
-                    "args": {
-                        "name": {
-                            "required": false,
-                            "description": "Unique registered name for the block.",
-                            "type": "string"
-                        },
-                        "context": {
-                            "required": false,
-                            "default": "view",
-                            "enum": [
-                                "edit"
-                            ],
-                            "description": "Scope under which the request is made; determines fields present in response.",
-                            "type": "string"
-                        },
-                        "attributes": {
-                            "required": false,
-                            "default": [],
-                            "description": "Attributes for core/tag-cloud block",
+                            "description": "Attributes for the block",
                             "type": "object"
                         },
                         "post_id": {