diff --git a/core/services/relay/evm/config_poller.go b/core/services/relay/evm/config_poller.go
index aada1242303..6d8d4588d07 100644
--- a/core/services/relay/evm/config_poller.go
+++ b/core/services/relay/evm/config_poller.go
@@ -138,6 +138,9 @@ func (cp *configPoller) LatestConfig(ctx context.Context, changedInBlock uint64)
 	if err != nil {
 		return ocrtypes.ContractConfig{}, err
 	}
+	if len(lgs) == 0 {
+		return ocrtypes.ContractConfig{}, errors.New("no logs found")
+	}
 	latestConfigSet, err := configFromLog(lgs[len(lgs)-1].Data)
 	if err != nil {
 		return ocrtypes.ContractConfig{}, err
diff --git a/core/services/relay/evm/config_poller_test.go b/core/services/relay/evm/config_poller_test.go
index 724c303210b..75e033dfeb7 100644
--- a/core/services/relay/evm/config_poller_test.go
+++ b/core/services/relay/evm/config_poller_test.go
@@ -64,12 +64,14 @@ func TestConfigPoller(t *testing.T) {
 	lp := logpoller.NewLogPoller(lorm, ethClient, lggr, 100*time.Millisecond, 1, 2, 2, 1000)
 	require.NoError(t, lp.Start(ctx))
 	t.Cleanup(func() { lp.Close() })
-	logPoller, err := NewConfigPoller(lggr, lp, ocrAddress)
+	configPoller, err := NewConfigPoller(lggr, lp, ocrAddress)
 	require.NoError(t, err)
 	// Should have no config to begin with.
-	_, config, err := logPoller.LatestConfigDetails(testutils.Context(t))
+	_, config, err := configPoller.LatestConfigDetails(testutils.Context(t))
 	require.NoError(t, err)
 	require.Equal(t, ocrtypes2.ConfigDigest{}, config)
+	_, err = configPoller.LatestConfig(testutils.Context(t), 0)
+	require.Error(t, err)
 	// Set the config
 	contractConfig := setConfig(t, median.OffchainConfig{
 		AlphaReportInfinite: false,
@@ -89,13 +91,13 @@ func TestConfigPoller(t *testing.T) {
 	var digest [32]byte
 	gomega.NewGomegaWithT(t).Eventually(func() bool {
 		b.Commit()
-		configBlock, digest, err = logPoller.LatestConfigDetails(testutils.Context(t))
+		configBlock, digest, err = configPoller.LatestConfigDetails(testutils.Context(t))
 		require.NoError(t, err)
 		return ocrtypes2.ConfigDigest{} != digest
 	}, testutils.WaitTimeout(t), 100*time.Millisecond).Should(gomega.BeTrue())
 
 	// Assert the config returned is the one we configured.
-	newConfig, err := logPoller.LatestConfig(testutils.Context(t), configBlock)
+	newConfig, err := configPoller.LatestConfig(testutils.Context(t), configBlock)
 	require.NoError(t, err)
 	// Note we don't check onchainConfig, as that is populated in the contract itself.
 	assert.Equal(t, digest, [32]byte(newConfig.ConfigDigest))
diff --git a/core/services/relay/evm/contract_transmitter.go b/core/services/relay/evm/contract_transmitter.go
index d4a2c6204ca..470b5bae076 100644
--- a/core/services/relay/evm/contract_transmitter.go
+++ b/core/services/relay/evm/contract_transmitter.go
@@ -93,6 +93,9 @@ func (oc *contractTransmitter) Transmit(ctx context.Context, reportCtx ocrtypes.
 	var rs [][32]byte
 	var ss [][32]byte
 	var vs [32]byte
+	if len(signatures) > 32 {
+		return errors.New("too many signatures, maximum is 32")
+	}
 	for i, as := range signatures {
 		r, s, v, err := evmutil.SplitSignature(as.Signature)
 		if err != nil {
@@ -138,6 +141,9 @@ func parseTransmitted(log []byte) ([32]byte, uint32, error) {
 	if err != nil {
 		return [32]byte{}, 0, err
 	}
+	if len(transmitted) < 2 {
+		return [32]byte{}, 0, errors.New("transmitted event log has too few arguments")
+	}
 	configDigest := *abi.ConvertType(transmitted[0], new([32]byte)).(*[32]byte)
 	epoch := *abi.ConvertType(transmitted[1], new(uint32)).(*uint32)
 	return configDigest, epoch, err
diff --git a/core/services/relay/evm/functions/config_poller.go b/core/services/relay/evm/functions/config_poller.go
index 4feff842ce3..f068f13cc77 100644
--- a/core/services/relay/evm/functions/config_poller.go
+++ b/core/services/relay/evm/functions/config_poller.go
@@ -162,6 +162,9 @@ func (cp *configPoller) LatestConfig(ctx context.Context, changedInBlock uint64)
 	if err != nil {
 		return ocrtypes.ContractConfig{}, err
 	}
+	if len(lgs) == 0 {
+		return ocrtypes.ContractConfig{}, errors.New("no logs found")
+	}
 	latestConfigSet, err := configFromLog(lgs[len(lgs)-1].Data, cp.pluginType)
 	if err != nil {
 		return ocrtypes.ContractConfig{}, err
diff --git a/core/services/relay/evm/functions/config_poller_test.go b/core/services/relay/evm/functions/config_poller_test.go
index b6de78b49df..b53b2751b15 100644
--- a/core/services/relay/evm/functions/config_poller_test.go
+++ b/core/services/relay/evm/functions/config_poller_test.go
@@ -89,6 +89,8 @@ func runTest(t *testing.T, pluginType functions.FunctionsPluginType, expectedDig
 	_, config, err := configPoller.LatestConfigDetails(testutils.Context(t))
 	require.NoError(t, err)
 	require.Equal(t, ocrtypes2.ConfigDigest{}, config)
+	_, err = configPoller.LatestConfig(testutils.Context(t), 0)
+	require.Error(t, err)
 
 	pluginConfig := &functionsConfig.ReportingPluginConfigWrapper{
 		Config: &functionsConfig.ReportingPluginConfig{
diff --git a/core/services/relay/evm/functions/contract_transmitter.go b/core/services/relay/evm/functions/contract_transmitter.go
index ecbe3c49f96..3c6399fbd83 100644
--- a/core/services/relay/evm/functions/contract_transmitter.go
+++ b/core/services/relay/evm/functions/contract_transmitter.go
@@ -99,6 +99,9 @@ func (oc *contractTransmitter) Transmit(ctx context.Context, reportCtx ocrtypes.
 	var rs [][32]byte
 	var ss [][32]byte
 	var vs [32]byte
+	if len(signatures) > 32 {
+		return errors.New("too many signatures, maximum is 32")
+	}
 	for i, as := range signatures {
 		r, s, v, err := evmutil.SplitSignature(as.Signature)
 		if err != nil {
@@ -169,6 +172,9 @@ func parseTransmitted(log []byte) ([32]byte, uint32, error) {
 	if err != nil {
 		return [32]byte{}, 0, err
 	}
+	if len(transmitted) < 2 {
+		return [32]byte{}, 0, errors.New("transmitted event log has too few arguments")
+	}
 	configDigest := *abi.ConvertType(transmitted[0], new([32]byte)).(*[32]byte)
 	epoch := *abi.ConvertType(transmitted[1], new(uint32)).(*uint32)
 	return configDigest, epoch, err
diff --git a/core/services/relay/evm/functions/contract_transmitter_test.go b/core/services/relay/evm/functions/contract_transmitter_test.go
index fb4a071de2a..6ce61c83a09 100644
--- a/core/services/relay/evm/functions/contract_transmitter_test.go
+++ b/core/services/relay/evm/functions/contract_transmitter_test.go
@@ -116,6 +116,14 @@ func TestContractTransmitter_Transmit_V1(t *testing.T) {
 	reportBytes, err := codec.EncodeReport(processedRequests)
 	require.NoError(t, err)
 
+	// success
 	require.NoError(t, ot.Transmit(testutils.Context(t), ocrtypes.ReportContext{}, reportBytes, []ocrtypes.AttributedOnchainSignature{}))
 	require.Equal(t, coordinatorAddress, ocrTransmitter.toAddress)
+
+	// failure on too many signatures
+	signatures := []ocrtypes.AttributedOnchainSignature{}
+	for i := 0; i < 33; i++ {
+		signatures = append(signatures, ocrtypes.AttributedOnchainSignature{})
+	}
+	require.Error(t, ot.Transmit(testutils.Context(t), ocrtypes.ReportContext{}, reportBytes, signatures))
 }