diff --git a/muted-tests.yml b/muted-tests.yml
index f7ebc1f4a6f69..9b312852b42b3 100644
--- a/muted-tests.yml
+++ b/muted-tests.yml
@@ -397,6 +397,9 @@ tests:
 - class: org.elasticsearch.xpack.esql.action.CrossClusterAsyncQueryStopIT
   method: testStopQueryLocal
   issue: https://github.com/elastic/elasticsearch/issues/121672
+- class: org.elasticsearch.xpack.esql.heap_attack.HeapAttackIT
+  method: testLookupExplosionBigStringManyMatches
+  issue: https://github.com/elastic/elasticsearch/issues/121465
 
 # Examples:
 #