diff --git a/.github/workflows/gnovm.yml b/.github/workflows/gnovm.yml
index 9b3173b95d4..6e286ea41fe 100644
--- a/.github/workflows/gnovm.yml
+++ b/.github/workflows/gnovm.yml
@@ -114,7 +114,7 @@ jobs:
         run: |
           ls
           # create coverage directory list separate by coma.
-          export COVERAGE_DIRS="$(ls -m | tr -d ' ')"
+          export COVERAGE_DIRS="$(ls -m | tr -d '[:blank:]')"
 
           echo $COVERAGE_DIRS