diff --git a/go.mod b/go.mod
index f15384a..7bfed95 100644
--- a/go.mod
+++ b/go.mod
@@ -3,5 +3,5 @@ module github.com/ivuorinen/tsm
 go 1.24
 
 require (
-	github.com/spf13/viper v1.18.2
+	github.com/spf13/viper v1.21.0
 )