diff --git a/test_libs/pyspec/tests/block_processing/test_process_attestation.py b/test_libs/pyspec/tests/block_processing/test_process_attestation.py
index 97eddb902d..763178717a 100644
--- a/test_libs/pyspec/tests/block_processing/test_process_attestation.py
+++ b/test_libs/pyspec/tests/block_processing/test_process_attestation.py
@@ -140,7 +140,7 @@ def test_bad_previous_crosslink(state):
     for _ in range(spec.MIN_ATTESTATION_INCLUSION_DELAY):
         next_slot(state)
 
-    state.current_crosslinks[attestation.data.crosslink.shard].end_epoch += 10
+    attestation.data.crosslink.parent_root = b'\x27' * 32
 
     pre_state, post_state = run_attestation_processing(state, attestation, False)