diff --git a/muted-tests.yml b/muted-tests.yml
index 0ef6db2b1dd89..7722d306d063c 100644
--- a/muted-tests.yml
+++ b/muted-tests.yml
@@ -545,9 +545,6 @@ tests:
   issue: https://github.com/elastic/elasticsearch/issues/121179
 - class: org.elasticsearch.xpack.application.CohereServiceUpgradeIT
   issue: https://github.com/elastic/elasticsearch/issues/121537
-- class: org.elasticsearch.xpack.esql.heap_attack.HeapAttackIT
-  method: testLookupExplosionBigStringManyMatches
-  issue: https://github.com/elastic/elasticsearch/issues/121465
 - class: org.elasticsearch.smoketest.DocsClientYamlTestSuiteIT
   method: test {yaml=reference/snapshot-restore/apis/get-snapshot-api/line_488}
   issue: https://github.com/elastic/elasticsearch/issues/121611
diff --git a/test/external-modules/esql-heap-attack/src/javaRestTest/java/org/elasticsearch/xpack/esql/heap_attack/HeapAttackIT.java b/test/external-modules/esql-heap-attack/src/javaRestTest/java/org/elasticsearch/xpack/esql/heap_attack/HeapAttackIT.java
index a71c3b5a6674f..d0b06942c1348 100644
--- a/test/external-modules/esql-heap-attack/src/javaRestTest/java/org/elasticsearch/xpack/esql/heap_attack/HeapAttackIT.java
+++ b/test/external-modules/esql-heap-attack/src/javaRestTest/java/org/elasticsearch/xpack/esql/heap_attack/HeapAttackIT.java
@@ -635,7 +635,8 @@ public void testLookupExplosion() throws IOException {
 
     public void testLookupExplosionManyMatches() throws IOException {
         assertCircuitBreaks(() -> {
-            Map<?, ?> result = lookupExplosion(1500, 10000);
+            // 1500, 10000 is enough locally, but some CI machines need more.
+            Map<?, ?> result = lookupExplosion(2000, 10000);
             logger.error("should have failed but got {}", result);
         });
     }
@@ -663,7 +664,8 @@ public void testLookupExplosionBigString() throws IOException {
 
     public void testLookupExplosionBigStringManyMatches() throws IOException {
         assertCircuitBreaks(() -> {
-            Map<?, ?> result = lookupExplosionBigString(500, 1);
+            // 500, 1 is enough to make it fail locally but some CI needs more
+            Map<?, ?> result = lookupExplosionBigString(800, 1);
             logger.error("should have failed but got {}", result);
         });
     }