diff --git a/composer.json b/composer.json
index e6ef82f..88b6908 100644
--- a/composer.json
+++ b/composer.json
@@ -18,7 +18,7 @@
 	},
 	"require-dev": {
 		"phpunit/phpunit": "7.5.1",
-		"fig/http-message-util": "^1.1",
+		"fig/http-message-util": "1.1.3",
 		"php-http/psr7-integration-tests": "dev-master"
 	},
 	"provide": {