diff --git a/entrypoint.sh b/entrypoint.sh
index f5c53ff..bbc5f70 100755
--- a/entrypoint.sh
+++ b/entrypoint.sh
@@ -8,7 +8,7 @@ if [ -n "$NPM_AUTH_TOKEN" ]; then
   NPM_REGISTRY_URL="${NPM_REGISTRY_URL-registry.npmjs.org}"
 
   # Allow registry.npmjs.org to be overridden with an environment variable
-  printf "//$NPM_REGISTRY_URL/:_authToken=$NPM_AUTH_TOKEN\nregistry=$NPM_REGISTRY_URL" > "$NPM_CONFIG_USERCONFIG"
+  printf "//%s/:_authToken=%s\\nregistry=%s" "$NPM_REGISTRY_URL" "$NPM_AUTH_TOKEN" "$NPM_REGISTRY_URL" > "$NPM_CONFIG_USERCONFIG"
   chmod 0600 "$NPM_CONFIG_USERCONFIG"
 fi
 
diff --git a/test/entrypoint.bats b/test/entrypoint.bats
index 319c8a7..38cb2e4 100644
--- a/test/entrypoint.bats
+++ b/test/entrypoint.bats
@@ -18,7 +18,7 @@ function setup() {
   export NPM_AUTH_TOKEN=NPM_AUTH_TOKEN
   run $GITHUB_WORKSPACE/entrypoint.sh help
   [ "$status" -eq 0 ]
-  [ "$(cat $NPM_CONFIG_USERCONFIG)" = "//registry.npmjs.org/:_authToken=NPM_AUTH_TOKEN" ]
+  [ "$(cat $NPM_CONFIG_USERCONFIG)" = $'//registry.npmjs.org/:_authToken=NPM_AUTH_TOKEN\nregistry=registry.npmjs.org' ]
 }
 
 @test "registry can be overridden" {
@@ -27,5 +27,5 @@ function setup() {
   export NPM_AUTH_TOKEN=NPM_AUTH_TOKEN
   run $GITHUB_WORKSPACE/entrypoint.sh help
   [ "$status" -eq 0 ]
-  [ "$(cat $NPM_CONFIG_USERCONFIG)" = "//someOtherRegistry.someDomain.net/:_authToken=NPM_AUTH_TOKEN" ]
+  [ "$(cat $NPM_CONFIG_USERCONFIG)" = $'//someOtherRegistry.someDomain.net/:_authToken=NPM_AUTH_TOKEN\nregistry=someOtherRegistry.someDomain.net' ]
 }