diff --git a/test/test-execute/exec-specifier-interpolation.service b/test/test-execute/exec-specifier-interpolation.service
index 4cb1b065187..2e8882c5ab1 100644
--- a/test/test-execute/exec-specifier-interpolation.service
+++ b/test/test-execute/exec-specifier-interpolation.service
@@ -4,4 +4,4 @@ Description=https://github.com/systemd/systemd/issues/2637
 
 [Service]
 Type=oneshot
-ExecStart=/bin/sh -x -c "! test -x perl || perl -e 'exit(!(qq{%%U} eq qq{\\x25U}))'"
+ExecStart=/bin/bash -x -c "[[ %%U == ?U ]]"