diff --git a/builtin/help.c b/builtin/help.c
index 991a8bb..12fb489 100644
--- a/builtin/help.c
+++ b/builtin/help.c
@@ -170,6 +170,7 @@ static void exec_man_cmd(const char *cmd, const char *page)
 	strbuf_addf(&shell_cmd, "%s %s", cmd, page);
 	execl(SHELL_PATH, SHELL_PATH, "-c", shell_cmd.buf, (char *)NULL);
 	warning(_("failed to exec '%s'"), cmd);
+	strbuf_release(&shell_cmd);
 }
 
 static void add_man_viewer(const char *name)