diff --git a/README.md b/README.md
index d3cf4df..e7fb385 100644
--- a/README.md
+++ b/README.md
@@ -34,7 +34,7 @@ AWS Codecommit:
 ```hcl
 module "pipeline" {
   source        = "aws-samples/pipeline/aws"
-  version       = "2.2.x"
+  version       = "2.3.x"
   pipeline_name = "pipeline-name"
   repo          = "codecommit-repo-name"
 }
@@ -70,7 +70,7 @@ module "pipeline" {
 
   codebuild_policy  = aws_iam_policy.this.arn
   build_timeout     = 10
-  terraform_version = "1.7.0"
+  terraform_version = "1.8.0"
   checkov_version   = "3.2.0"
   tflint_version    = "0.55.0"
 
diff --git a/variables.tf b/variables.tf
index 8aa4a96..3c44bcc 100644
--- a/variables.tf
+++ b/variables.tf
@@ -56,6 +56,10 @@ variable "checkov_skip" {
 variable "checkov_version" {
   type    = string
   default = "3.2.0"
+  validation {
+    condition     = can(regex("^\\d+\\.\\d+\\.\\d+$", var.checkov_version))
+    error_message = "checkov version must use format x.y.z"
+  }
 }
 
 variable "codebuild_policy" {
@@ -121,16 +125,28 @@ variable "tags" {
 variable "tagnag_version" {
   type    = string
   default = "0.7.9"
+  validation {
+    condition     = can(regex("^\\d+\\.\\d+\\.\\d+$", var.tagnag_version))
+    error_message = "tagnag version must use format x.y.z"
+  }
 }
 
 variable "terraform_version" {
   type    = string
-  default = "1.7.0"
+  default = "1.8.0"
+  validation {
+    condition     = can(regex("^\\d+\\.\\d+\\.\\d+$", var.terraform_version))
+    error_message = "terraform version must use format x.y.z"
+  }
 }
 
 variable "tflint_version" {
   type    = string
   default = "0.55.0"
+  validation {
+    condition     = can(regex("^\\d+\\.\\d+\\.\\d+$", var.tflint_version))
+    error_message = "tflint version must use format x.y.z"
+  }
 }
 
 variable "vpc" {