diff --git a/src/net.h b/src/net.h
index 96f04d83e..7839b75a8 100644
--- a/src/net.h
+++ b/src/net.h
@@ -469,6 +469,13 @@ public:
     virtual bool SendMessages(CNode* pnode, std::atomic<bool>& interrupt) = 0;
     virtual void InitializeNode(CNode* pnode) = 0;
     virtual void FinalizeNode(NodeId id, bool& update_connection_time) = 0;
+
+protected:
+    /**
+     * Protected destructor so that instances can only be deleted by derived classes.
+     * If that restriction is no longer desired, this should be made public and virtual.
+     */
+    ~NetEventsInterface() = default;
 };
 
 enum
diff --git a/src/net_processing.h b/src/net_processing.h
index ff1ebc59d..11543129c 100644
--- a/src/net_processing.h
+++ b/src/net_processing.h
@@ -35,7 +35,7 @@ static constexpr int64_t EXTRA_PEER_CHECK_INTERVAL = 45;
 /** Minimum time an outbound-peer-eviction candidate must be connected for, in order to evict, in seconds */
 static constexpr int64_t MINIMUM_CONNECT_TIME = 30;
 
-class PeerLogicValidation : public CValidationInterface, public NetEventsInterface {
+class PeerLogicValidation final : public CValidationInterface, public NetEventsInterface {
 private:
     CConnman* const connman;
 
diff --git a/src/validationinterface.h b/src/validationinterface.h
index 56ea698a2..63097166a 100644
--- a/src/validationinterface.h
+++ b/src/validationinterface.h
@@ -55,6 +55,11 @@ void SyncWithValidationInterfaceQueue();
 
 class CValidationInterface {
 protected:
+    /**
+     * Protected destructor so that instances can only be deleted by derived classes.
+     * If that restriction is no longer desired, this should be made public and virtual.
+     */
+    ~CValidationInterface() = default;
     /**
      * Notifies listeners of updated block chain tip
      *