diff --git a/Cargo.toml b/Cargo.toml
index 924ebd9..6189394 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -40,7 +40,7 @@ data-encoding = "2.2.1"
 lazy_static = "1.4"
 nom = "6.0"
 rusticata-macros = "3.0"
-num-bigint = "0.3"
+num-bigint = "0.4"
 ring = { version="0.16", optional=true }
 rustversion = "1.0"
 der-parser = { version = "5.0.0-beta1", features=["bigint"] }