diff --git a/composer.json b/composer.json
index bd3933a..7c56768 100644
--- a/composer.json
+++ b/composer.json
@@ -19,7 +19,7 @@
 	},
 	"require-dev": {
 		"cvuorinen/phpdoc-markdown-public": "^0.2.0",
-		"phpseclib/phpseclib": "^2.0",
+		"phpseclib/phpseclib": "^2.0 || ^3.0",
 		"phpunit/phpunit": "^9.0"
 	},
 	"autoload": {