diff --git a/tests/net/gnrc_sixlowpan_frag_sfr_congure/main.c b/tests/net/gnrc_sixlowpan_frag_sfr_congure/main.c
index a3cd545d43..92433293a3 100644
--- a/tests/net/gnrc_sixlowpan_frag_sfr_congure/main.c
+++ b/tests/net/gnrc_sixlowpan_frag_sfr_congure/main.c
@@ -802,6 +802,10 @@ int main(void)
 {
     _tests_init();
 
+    /* work around issue in _check_congure_snd_msg(): the assert for
+     * time > o will not work when the time is 0 */
+    while (xtimer_now_usec() / US_PER_MS == 0) { }
+
     TESTS_START();
     TESTS_RUN(tests_gnrc_sixlowpan_frag_sfr_congure_integration());
     TESTS_END();