diff --git a/.pre-commit-hooks.yaml b/.pre-commit-hooks.yaml
index 746a676..492b559 100644
--- a/.pre-commit-hooks.yaml
+++ b/.pre-commit-hooks.yaml
@@ -79,6 +79,7 @@
 - id: terraform_tfsec
   name: Terraform validate with tfsec
   description: Static analysis of Terraform templates to spot potential security issues.
+  require_serial: true
   entry: terraform_tfsec.sh
   language: script
 
diff --git a/terraform_tfsec.sh b/terraform_tfsec.sh
index 6c6ee25..c742f32 100755
--- a/terraform_tfsec.sh
+++ b/terraform_tfsec.sh
@@ -6,13 +6,13 @@ main() {
   parse_cmdline_ "$@"
 
   # propagate $FILES to custom function
-  tfsec_ "$ARGS" "$FILES"
+  tfsec_ "$ARGS" "${FILES[*]}"
 }
 
 tfsec_() {
   # consume modified files passed from pre-commit so that
   # tfsec runs against only those relevant directories
-  for file_with_path in $FILES; do
+  for file_with_path in ${FILES[*]}; do
     file_with_path="${file_with_path// /__REPLACED__SPACE__}"
     paths[index]=$(dirname "$file_with_path")