diff --git a/tests/foreman/api/test_errata.py b/tests/foreman/api/test_errata.py
index 5c00f7114c2..2658fe5771a 100644
--- a/tests/foreman/api/test_errata.py
+++ b/tests/foreman/api/test_errata.py
@@ -202,15 +202,19 @@ def test_positive_install_multiple_in_host(
     rhel_contenthost.register_contenthost(function_org.name, activation_key.name, function_lce.name)
     rhel_contenthost.run(r'subscription-manager repos --enable \*')
     assert rhel_contenthost.subscribed
+    # Installing outdated custom packages:
     for package in constants.FAKE_9_YUM_OUTDATED_PACKAGES:
         assert rhel_contenthost.run(f'yum install -y {package}').status == 0
-    applicable_errata_count = rhel_contenthost.applicable_errata_count
-    assert applicable_errata_count > 1
+        assert rhel_contenthost.run(f'rpm -q {package}').status == 0
     rhel_contenthost.add_rex_key(satellite=module_target_sat)
+    original_applicable_count = rhel_contenthost.applicable_errata_count
 
-    # Each applicable errata will be installed sequentially,
+    # Each errata will be installed sequentially,
     # after each install, applicable-errata-count should drop by one.
-    for errata in settings.repos.yum_9.errata[1:4]:
+    installed_errata_count = 0
+    for errata in constants.FAKE_9_YUM_SECURITY_ERRATUM:
+        applicable_errata_count = rhel_contenthost.applicable_errata_count
+        assert applicable_errata_count > 1
         task_id = module_target_sat.api.JobInvocation().run(
             data={
                 'feature': 'katello_errata_install',
@@ -227,6 +231,12 @@ def test_positive_install_multiple_in_host(
         )
         applicable_errata_count -= 1
         assert rhel_contenthost.applicable_errata_count == applicable_errata_count
+        installed_errata_count += 1
+
+    assert (
+        rhel_contenthost.applicable_errata_count
+        == original_applicable_count - installed_errata_count
+    )
 
 
 @pytest.mark.tier3