diff --git a/framework/extensions/src/main/java/org/apache/cloudstack/framework/extensions/manager/ExtensionsManagerImpl.java b/framework/extensions/src/main/java/org/apache/cloudstack/framework/extensions/manager/ExtensionsManagerImpl.java
index 1422338ddc9..f6fd08b6da2 100644
--- a/framework/extensions/src/main/java/org/apache/cloudstack/framework/extensions/manager/ExtensionsManagerImpl.java
+++ b/framework/extensions/src/main/java/org/apache/cloudstack/framework/extensions/manager/ExtensionsManagerImpl.java
@@ -1663,14 +1663,14 @@ public class ExtensionsManagerImpl extends ManagerBase implements ExtensionsMana
     public List<String> getExtensionReservedResourceDetails(long extensionId) {
         ExtensionDetailsVO detailsVO = extensionDetailsDao.findDetail(extensionId,
                 ApiConstants.RESERVED_RESOURCE_DETAILS);
-        if (detailsVO == null || !StringUtils.isNotBlank(detailsVO.getValue())) {
-            return Collections.emptyList();
-        }
         List<String> reservedDetails = new ArrayList<>();
-        String[] parts = detailsVO.getValue().split(",");
-        for (String part : parts) {
-            if (StringUtils.isNotBlank(part)) {
-                reservedDetails.add(part.trim());
+        if (detailsVO != null && StringUtils.isNotBlank(detailsVO.getValue())) {
+            String[] parts = detailsVO.getValue().split(",");
+            for (String part : parts) {
+                String trimmedPart = part.trim();
+                if (StringUtils.isNotBlank(trimmedPart)) {
+                    reservedDetails.add(trimmedPart);
+                }
             }
         }
         addInbuiltExtensionReservedResourceDetails(extensionId, reservedDetails);
diff --git a/server/src/main/java/com/cloud/vm/snapshot/VMSnapshotManagerImpl.java b/server/src/main/java/com/cloud/vm/snapshot/VMSnapshotManagerImpl.java
index bfec3247a7b..baa74128ce3 100644
--- a/server/src/main/java/com/cloud/vm/snapshot/VMSnapshotManagerImpl.java
+++ b/server/src/main/java/com/cloud/vm/snapshot/VMSnapshotManagerImpl.java
@@ -764,6 +764,13 @@ public class VMSnapshotManagerImpl extends MutualExclusiveIdsManagerBase impleme
                             "In order to revert to a Snapshot without memory you need to first stop the Instance.");
         }
 
+        if (userVm.getState() == VirtualMachine.State.Running && vmSnapshotVo.getType() == VMSnapshot.Type.Disk) {
+            throw new InvalidParameterValueException(
+                    "Reverting to the Instance Snapshot is not allowed for running Instances as this would result in an Instance state change. " +
+                            "For running Instances only Snapshots with memory can be reverted. " +
+                            "In order to revert to a Snapshot without memory you need to first stop the Instance.");
+        }
+
         if (userVm.getState() == VirtualMachine.State.Stopped && vmSnapshotVo.getType() == VMSnapshot.Type.DiskAndMemory) {
             throw new InvalidParameterValueException(
                     "Reverting to the Instance Snapshot is not allowed for stopped Instances when the Snapshot contains memory as this would result in an Instance state change. " +
diff --git a/server/src/test/java/org/apache/cloudstack/vm/UnmanagedVMsManagerImplTest.java b/server/src/test/java/org/apache/cloudstack/vm/UnmanagedVMsManagerImplTest.java
index 874bce0f95e..bee6c4ad257 100644
--- a/server/src/test/java/org/apache/cloudstack/vm/UnmanagedVMsManagerImplTest.java
+++ b/server/src/test/java/org/apache/cloudstack/vm/UnmanagedVMsManagerImplTest.java
@@ -169,10 +169,10 @@ import com.cloud.vm.ImportVMTaskVO;
 import com.cloud.vm.NicProfile;
 import com.cloud.vm.UserVmManager;
 import com.cloud.vm.UserVmVO;
+import com.cloud.vm.VmDetailConstants;
 import com.cloud.vm.VMInstanceDetailVO;
 import com.cloud.vm.VMInstanceVO;
 import com.cloud.vm.VirtualMachine;
-import com.cloud.vm.VmDetailConstants;
 import com.cloud.vm.dao.NicDao;
 import com.cloud.vm.dao.UserVmDao;
 import com.cloud.vm.dao.VMInstanceDao;