diff --git a/tests/filter_tmpdir.sh b/tests/filter_tmpdir.sh
index cb7a66c1f6ada434a1389398dfe8e9cfc7387d48..fc7fcdd583011ff3bb829531314bc491878037be 100755
--- a/tests/filter_tmpdir.sh
+++ b/tests/filter_tmpdir.sh
@@ -1,3 +1,3 @@
-#!/bin/bash -eu
+#!/bin/sh -eu
 
 exec sed -e "s&${TMPDIR:-/tmp}/[a-z0-9_./]*&\$TMPFILE&"