diff --git a/src/Makefile.test_fuzz.include b/src/Makefile.test_fuzz.include
index 0865120842..06734546e9 100644
--- a/src/Makefile.test_fuzz.include
+++ b/src/Makefile.test_fuzz.include
@@ -18,6 +18,7 @@ libtest_fuzz_a_CXXFLAGS = $(AM_CXXFLAGS) $(PIE_FLAGS)
 libtest_fuzz_a_SOURCES = \
   test/fuzz/fuzz.cpp \
   test/util/mining.cpp \
+  test/fuzz/util.cpp \
   $(TEST_FUZZ_H)
 
 LIBTEST_FUZZ += $(LIBBITCOIN_SERVER)
diff --git a/src/test/fuzz/process_message.cpp b/src/test/fuzz/process_message.cpp
index c8ab69bf2b..c32e659502 100644
--- a/src/test/fuzz/process_message.cpp
+++ b/src/test/fuzz/process_message.cpp
@@ -67,10 +67,12 @@ void fuzz_target(const std::vector<uint8_t>& buffer, const std::string& LIMIT_TO
         return;
     }
     CNode& p2p_node = *ConsumeNodeAsUniquePtr(fuzzed_data_provider).release();
-    FillNode(fuzzed_data_provider, p2p_node);
-    p2p_node.fSuccessfullyConnected = true;
+
+    const bool successfully_connected{true};
+    p2p_node.fSuccessfullyConnected = successfully_connected;
     connman.AddTestNode(p2p_node);
     g_setup->m_node.peerman->InitializeNode(&p2p_node);
+    FillNode(fuzzed_data_provider, p2p_node, /* init_version */ successfully_connected);
 
     // fuzzed_data_provider is fully consumed after this call, don't use it
     CDataStream random_bytes_data_stream{fuzzed_data_provider.ConsumeRemainingBytes<unsigned char>(), SER_NETWORK, PROTOCOL_VERSION};
diff --git a/src/test/fuzz/process_messages.cpp b/src/test/fuzz/process_messages.cpp
index 2222e9ed4f..af28e785ee 100644
--- a/src/test/fuzz/process_messages.cpp
+++ b/src/test/fuzz/process_messages.cpp
@@ -45,10 +45,11 @@ FUZZ_TARGET_INIT(process_messages, initialize_process_messages)
         peers.push_back(ConsumeNodeAsUniquePtr(fuzzed_data_provider, i).release());
         CNode& p2p_node = *peers.back();
 
-        FillNode(fuzzed_data_provider, p2p_node);
-        p2p_node.fSuccessfullyConnected = true;
+        const bool successfully_connected{true};
+        p2p_node.fSuccessfullyConnected = successfully_connected;
         p2p_node.fPauseSend = false;
         g_setup->m_node.peerman->InitializeNode(&p2p_node);
+        FillNode(fuzzed_data_provider, p2p_node, /* init_version */ successfully_connected);
 
         connman.AddTestNode(p2p_node);
     }
diff --git a/src/test/fuzz/util.cpp b/src/test/fuzz/util.cpp
new file mode 100644
index 0000000000..9604c49e7a
--- /dev/null
+++ b/src/test/fuzz/util.cpp
@@ -0,0 +1,25 @@
+// Copyright (c) 2021 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include <test/fuzz/util.h>
+#include <version.h>
+
+void FillNode(FuzzedDataProvider& fuzzed_data_provider, CNode& node, bool init_version) noexcept
+{
+    const ServiceFlags remote_services = ConsumeWeakEnum(fuzzed_data_provider, ALL_SERVICE_FLAGS);
+    const NetPermissionFlags permission_flags = ConsumeWeakEnum(fuzzed_data_provider, ALL_NET_PERMISSION_FLAGS);
+    const int32_t version = fuzzed_data_provider.ConsumeIntegralInRange<int32_t>(MIN_PEER_PROTO_VERSION, std::numeric_limits<int32_t>::max());
+    const bool filter_txs = fuzzed_data_provider.ConsumeBool();
+
+    node.nServices = remote_services;
+    node.m_permissionFlags = permission_flags;
+    if (init_version) {
+        node.nVersion = version;
+        node.SetSendVersion(std::min(version, PROTOCOL_VERSION));
+    }
+    if (node.m_tx_relay != nullptr) {
+        LOCK(node.m_tx_relay->cs_filter);
+        node.m_tx_relay->fRelayTxes = filter_txs;
+    }
+}
diff --git a/src/test/fuzz/util.h b/src/test/fuzz/util.h
index 556a81f38d..fd3b06179d 100644
--- a/src/test/fuzz/util.h
+++ b/src/test/fuzz/util.h
@@ -316,24 +316,9 @@ auto ConsumeNode(FuzzedDataProvider& fuzzed_data_provider, const std::optional<N
         return CNode{node_id, local_services, socket, address, keyed_net_group, local_host_nonce, addr_bind, addr_name, inbound, block_relay_only};
     }
 }
-inline std::unique_ptr<CNode> ConsumeNodeAsUniquePtr(FuzzedDataProvider& fdp, const std::optional<NodeId>& node_id_in = nullopt) { return ConsumeNode<true>(fdp, node_id_in); }
+inline std::unique_ptr<CNode> ConsumeNodeAsUniquePtr(FuzzedDataProvider& fdp, const std::optional<NodeId>& node_id_in = std::nullopt) { return ConsumeNode<true>(fdp, node_id_in); }
 
-inline void FillNode(FuzzedDataProvider& fuzzed_data_provider, CNode& node, const std::optional<int32_t>& version_in = std::nullopt) noexcept
-{
-    const ServiceFlags remote_services = ConsumeWeakEnum(fuzzed_data_provider, ALL_SERVICE_FLAGS);
-    const NetPermissionFlags permission_flags = ConsumeWeakEnum(fuzzed_data_provider, ALL_NET_PERMISSION_FLAGS);
-    const int32_t version = version_in.value_or(fuzzed_data_provider.ConsumeIntegral<int32_t>());
-    const bool filter_txs = fuzzed_data_provider.ConsumeBool();
-
-    node.nServices = remote_services;
-    node.m_permissionFlags = permission_flags;
-    node.nVersion = version;
-    node.SetSendVersion(version);
-    if (node.m_tx_relay != nullptr) {
-        LOCK(node.m_tx_relay->cs_filter);
-        node.m_tx_relay->fRelayTxes = filter_txs;
-    }
-}
+void FillNode(FuzzedDataProvider& fuzzed_data_provider, CNode& node, bool init_version) noexcept;
 
 inline void InitializeFuzzingContext(const std::string& chain_name = CBaseChainParams::REGTEST)
 {