diff --git a/x-pack/test/case_api_integration/security_and_spaces/tests/common/cases/patch_cases.ts b/x-pack/test/case_api_integration/security_and_spaces/tests/common/cases/patch_cases.ts
index 6b370117c447a..e2a7512940250 100644
--- a/x-pack/test/case_api_integration/security_and_spaces/tests/common/cases/patch_cases.ts
+++ b/x-pack/test/case_api_integration/security_and_spaces/tests/common/cases/patch_cases.ts
@@ -805,7 +805,7 @@ export default ({ getService }: FtrProviderContext): void => {
           const signals = await getSignalsByIds(supertest, [id]);
 
           const alert = signals.hits.hits[0];
-          expect(alert._source.signal.status).eql('open');
+          expect(alert._source?.signal.status).eql('open');
 
           const caseUpdated = await createComment({
             supertest,
@@ -846,7 +846,7 @@ export default ({ getService }: FtrProviderContext): void => {
             .send(getQuerySignalIds([alert._id]))
             .expect(200);
 
-          expect(updatedAlert.hits.hits[0]._source.signal.status).eql('in-progress');
+          expect(updatedAlert.hits.hits[0]._source?.signal.status).eql('in-progress');
         });
 
         it('does NOT updates alert status when the status is updated and syncAlerts=false', async () => {
@@ -863,7 +863,7 @@ export default ({ getService }: FtrProviderContext): void => {
           const signals = await getSignalsByIds(supertest, [id]);
 
           const alert = signals.hits.hits[0];
-          expect(alert._source.signal.status).eql('open');
+          expect(alert._source?.signal.status).eql('open');
 
           const caseUpdated = await createComment({
             supertest,
@@ -899,7 +899,7 @@ export default ({ getService }: FtrProviderContext): void => {
             .send(getQuerySignalIds([alert._id]))
             .expect(200);
 
-          expect(updatedAlert.hits.hits[0]._source.signal.status).eql('open');
+          expect(updatedAlert.hits.hits[0]._source?.signal.status).eql('open');
         });
 
         it('it updates alert status when syncAlerts is turned on', async () => {
@@ -916,7 +916,7 @@ export default ({ getService }: FtrProviderContext): void => {
           const signals = await getSignalsByIds(supertest, [id]);
 
           const alert = signals.hits.hits[0];
-          expect(alert._source.signal.status).eql('open');
+          expect(alert._source?.signal.status).eql('open');
 
           const caseUpdated = await createComment({
             supertest,
@@ -970,7 +970,7 @@ export default ({ getService }: FtrProviderContext): void => {
             .send(getQuerySignalIds([alert._id]))
             .expect(200);
 
-          expect(updatedAlert.hits.hits[0]._source.signal.status).eql('in-progress');
+          expect(updatedAlert.hits.hits[0]._source?.signal.status).eql('in-progress');
         });
 
         it('it does NOT updates alert status when syncAlerts is turned off', async () => {
@@ -983,7 +983,7 @@ export default ({ getService }: FtrProviderContext): void => {
           const signals = await getSignalsByIds(supertest, [id]);
 
           const alert = signals.hits.hits[0];
-          expect(alert._source.signal.status).eql('open');
+          expect(alert._source?.signal.status).eql('open');
 
           const caseUpdated = await createComment({
             supertest,
diff --git a/x-pack/test/case_api_integration/security_and_spaces/tests/common/comments/post_comment.ts b/x-pack/test/case_api_integration/security_and_spaces/tests/common/comments/post_comment.ts
index f22ce54de193a..ecd05a2717e08 100644
--- a/x-pack/test/case_api_integration/security_and_spaces/tests/common/comments/post_comment.ts
+++ b/x-pack/test/case_api_integration/security_and_spaces/tests/common/comments/post_comment.ts
@@ -369,7 +369,7 @@ export default ({ getService }: FtrProviderContext): void => {
         const signals = await getSignalsByIds(supertest, [id]);
 
         const alert = signals.hits.hits[0];
-        expect(alert._source.signal.status).eql('open');
+        expect(alert._source?.signal.status).eql('open');
 
         await createComment({
           supertest,
@@ -424,7 +424,7 @@ export default ({ getService }: FtrProviderContext): void => {
         const signals = await getSignalsByIds(supertest, [id]);
 
         const alert = signals.hits.hits[0];
-        expect(alert._source.signal.status).eql('open');
+        expect(alert._source?.signal.status).eql('open');
 
         await createComment({
           supertest,
diff --git a/x-pack/test/detection_engine_api_integration/security_and_spaces/tests/create_ml.ts b/x-pack/test/detection_engine_api_integration/security_and_spaces/tests/create_ml.ts
index d371a11ba595f..a03bd07c86020 100644
--- a/x-pack/test/detection_engine_api_integration/security_and_spaces/tests/create_ml.ts
+++ b/x-pack/test/detection_engine_api_integration/security_and_spaces/tests/create_ml.ts
@@ -100,6 +100,10 @@ export default ({ getService }: FtrProviderContext) => {
       const signalsOpen = await getOpenSignals(supertest, es, createdRule);
       expect(signalsOpen.hits.hits.length).eql(1);
       const signal = signalsOpen.hits.hits[0];
+      if (!signal._source) {
+        return expect(signal._source).to.be.ok();
+      }
+
       expect(signal._source).eql({
         '@timestamp': signal._source['@timestamp'],
         actual: [1],