diff --git a/CHANGELOG.md b/CHANGELOG.md
index a6bdaf81df..e068651d4b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -12,6 +12,9 @@ See [RELEASE](./RELEASE.md) for workflow instructions.
 * [#6152](https://github.com/spacemeshos/go-spacemesh/pull/6152) Fixed a bug where in rare cases the node would panic
   due to the closing of a closed channel in the fetcher.
 
+* [#6142](https://github.com/spacemeshos/go-spacemesh/pull/6142) Fix node not dropping peers that are broadcasting
+  invalid ATXs.
+
 ## Release v1.6.3
 
 ### Improvements
diff --git a/activation/handler.go b/activation/handler.go
index f79daa678f..1bc12be966 100644
--- a/activation/handler.go
+++ b/activation/handler.go
@@ -275,7 +275,7 @@ func (h *Handler) handleAtx(
 
 	opaqueAtx, err := h.decodeATX(msg)
 	if err != nil {
-		return nil, fmt.Errorf("decoding ATX: %w", err)
+		return nil, fmt.Errorf("%w: decoding ATX: %w", pubsub.ErrValidationReject, err)
 	}
 	id := opaqueAtx.ID()
 
diff --git a/activation/handler_test.go b/activation/handler_test.go
index d5b03b9be0..2bfed5ea84 100644
--- a/activation/handler_test.go
+++ b/activation/handler_test.go
@@ -360,7 +360,7 @@ func TestHandler_HandleGossipAtx(t *testing.T) {
 	atxHdlr.mockFetch.EXPECT().GetPoetProof(gomock.Any(), types.Hash32(second.NIPost.PostMetadata.Challenge))
 	atxHdlr.mockFetch.EXPECT().GetAtxs(gomock.Any(), []types.ATXID{second.PrevATXID}, gomock.Any())
 	err = atxHdlr.HandleGossipAtx(context.Background(), "", codec.MustEncode(second))
-	require.ErrorContains(t, err, "syntactically invalid based on deps")
+	require.ErrorIs(t, err, sql.ErrNotFound)
 
 	// valid first comes in
 	atxHdlr.expectAtxV1(first, sig.NodeID())
@@ -514,6 +514,7 @@ func TestHandler_HandleSyncedAtx(t *testing.T) {
 		err := atxHdlr.HandleSyncedAtx(context.Background(), atx.ID().Hash32(), p2p.NoPeer, buf)
 		require.ErrorIs(t, err, errMalformedData)
 		require.ErrorContains(t, err, "invalid atx signature")
+		require.ErrorIs(t, err, pubsub.ErrValidationReject)
 	})
 	t.Run("atx V2", func(t *testing.T) {
 		t.Parallel()
@@ -857,12 +858,14 @@ func TestHandler_DecodeATX(t *testing.T) {
 		atxHdlr := newTestHandler(t, types.RandomATXID())
 		_, err := atxHdlr.decodeATX(nil)
 		require.ErrorIs(t, err, errMalformedData)
+		require.ErrorIs(t, err, pubsub.ErrValidationReject)
 	})
 	t.Run("malformed atx", func(t *testing.T) {
 		t.Parallel()
 		atxHdlr := newTestHandler(t, types.RandomATXID())
 		_, err := atxHdlr.decodeATX([]byte("malformed"))
 		require.ErrorIs(t, err, errMalformedData)
+		require.ErrorIs(t, err, pubsub.ErrValidationReject)
 	})
 	t.Run("v1", func(t *testing.T) {
 		t.Parallel()
@@ -893,5 +896,6 @@ func TestHandler_DecodeATX(t *testing.T) {
 		atx.PublishEpoch = 9
 		_, err := atxHdlr.decodeATX(codec.MustEncode(atx))
 		require.ErrorIs(t, err, errMalformedData)
+		require.ErrorIs(t, err, pubsub.ErrValidationReject)
 	})
 }
diff --git a/activation/handler_v1.go b/activation/handler_v1.go
index cefff79e1b..9724da932a 100644
--- a/activation/handler_v1.go
+++ b/activation/handler_v1.go
@@ -21,6 +21,7 @@ import (
 	"github.com/spacemeshos/go-spacemesh/log"
 	mwire "github.com/spacemeshos/go-spacemesh/malfeasance/wire"
 	"github.com/spacemeshos/go-spacemesh/p2p"
+	"github.com/spacemeshos/go-spacemesh/p2p/pubsub"
 	"github.com/spacemeshos/go-spacemesh/signing"
 	"github.com/spacemeshos/go-spacemesh/sql"
 	"github.com/spacemeshos/go-spacemesh/sql/atxs"
@@ -622,7 +623,7 @@ func (h *HandlerV1) processATX(
 	received time.Time,
 ) (*mwire.MalfeasanceProof, error) {
 	if !h.edVerifier.Verify(signing.ATX, watx.SmesherID, watx.SignedBytes(), watx.Signature) {
-		return nil, fmt.Errorf("invalid atx signature: %w", errMalformedData)
+		return nil, fmt.Errorf("%w: invalid atx signature: %w", pubsub.ErrValidationReject, errMalformedData)
 	}
 
 	existing, _ := h.cdb.GetAtx(watx.ID())
@@ -638,7 +639,7 @@ func (h *HandlerV1) processATX(
 	)
 
 	if err := h.syntacticallyValidate(ctx, watx); err != nil {
-		return nil, fmt.Errorf("atx %s syntactically invalid: %w", watx.ID(), err)
+		return nil, fmt.Errorf("%w: validating atx %s: %w", pubsub.ErrValidationReject, watx.ID(), err)
 	}
 
 	poetRef, atxIDs := collectAtxDeps(h.goldenATXID, watx)
@@ -649,7 +650,7 @@ func (h *HandlerV1) processATX(
 
 	leaves, effectiveNumUnits, proof, err := h.syntacticallyValidateDeps(ctx, watx)
 	if err != nil {
-		return nil, fmt.Errorf("atx %s syntactically invalid based on deps: %w", watx.ID(), err)
+		return nil, fmt.Errorf("%w: validating atx %s (deps): %w", pubsub.ErrValidationReject, watx.ID(), err)
 	}
 	if proof != nil {
 		return proof, nil
@@ -712,7 +713,7 @@ func (h *HandlerV1) registerHashes(peer p2p.Peer, poetRef types.Hash32, atxIDs [
 // fetchReferences makes sure that the referenced poet proof and ATXs are available.
 func (h *HandlerV1) fetchReferences(ctx context.Context, poetRef types.Hash32, atxIDs []types.ATXID) error {
 	if err := h.fetcher.GetPoetProof(ctx, poetRef); err != nil {
-		return fmt.Errorf("missing poet proof (%s): %w", poetRef.ShortString(), err)
+		return fmt.Errorf("fetching poet proof (%s): %w", poetRef.ShortString(), err)
 	}
 
 	if len(atxIDs) == 0 {
diff --git a/activation/handler_v1_test.go b/activation/handler_v1_test.go
index 02cef11cd4..1ef2918573 100644
--- a/activation/handler_v1_test.go
+++ b/activation/handler_v1_test.go
@@ -16,8 +16,10 @@ import (
 	"github.com/spacemeshos/go-spacemesh/codec"
 	"github.com/spacemeshos/go-spacemesh/common/types"
 	"github.com/spacemeshos/go-spacemesh/datastore"
+	"github.com/spacemeshos/go-spacemesh/fetch"
 	mwire "github.com/spacemeshos/go-spacemesh/malfeasance/wire"
 	"github.com/spacemeshos/go-spacemesh/p2p"
+	"github.com/spacemeshos/go-spacemesh/p2p/pubsub"
 	"github.com/spacemeshos/go-spacemesh/signing"
 	"github.com/spacemeshos/go-spacemesh/sql"
 	"github.com/spacemeshos/go-spacemesh/sql/atxs"
@@ -857,4 +859,18 @@ func TestHandlerV1_FetchesReferences(t *testing.T) {
 		atxHdlr.mockFetch.EXPECT().GetAtxs(gomock.Any(), atxs, gomock.Any()).Return(errors.New("oh"))
 		require.Error(t, atxHdlr.fetchReferences(context.Background(), poet, atxs))
 	})
+	t.Run("reject ATX when dependency ATX is rejected", func(t *testing.T) {
+		t.Parallel()
+		atxHdlr := newV1TestHandler(t, goldenATXID)
+
+		poet := types.RandomHash()
+		atxs := []types.ATXID{types.RandomATXID(), types.RandomATXID()}
+		var batchErr fetch.BatchError
+		batchErr.Add(atxs[0].Hash32(), pubsub.ErrValidationReject)
+
+		atxHdlr.mockFetch.EXPECT().GetPoetProof(gomock.Any(), poet)
+		atxHdlr.mockFetch.EXPECT().GetAtxs(gomock.Any(), atxs, gomock.Any()).Return(&batchErr)
+
+		require.ErrorIs(t, atxHdlr.fetchReferences(context.Background(), poet, atxs), pubsub.ErrValidationReject)
+	})
 }
diff --git a/activation/handler_v2.go b/activation/handler_v2.go
index a369c50aaf..b432dcba60 100644
--- a/activation/handler_v2.go
+++ b/activation/handler_v2.go
@@ -23,6 +23,7 @@ import (
 	"github.com/spacemeshos/go-spacemesh/log"
 	mwire "github.com/spacemeshos/go-spacemesh/malfeasance/wire"
 	"github.com/spacemeshos/go-spacemesh/p2p"
+	"github.com/spacemeshos/go-spacemesh/p2p/pubsub"
 	"github.com/spacemeshos/go-spacemesh/signing"
 	"github.com/spacemeshos/go-spacemesh/sql"
 	"github.com/spacemeshos/go-spacemesh/sql/atxs"
@@ -90,7 +91,7 @@ func (h *HandlerV2) processATX(
 	)
 
 	if err := h.syntacticallyValidate(ctx, watx); err != nil {
-		return nil, fmt.Errorf("atx %s syntactically invalid: %w", watx.ID(), err)
+		return nil, fmt.Errorf("%w: validating atx %s: %w", pubsub.ErrValidationReject, watx.ID(), err)
 	}
 
 	poetRef, atxIDs := h.collectAtxDeps(watx)
@@ -101,17 +102,17 @@ func (h *HandlerV2) processATX(
 
 	baseTickHeight, err := h.validatePositioningAtx(watx.PublishEpoch, h.goldenATXID, watx.PositioningATX)
 	if err != nil {
-		return nil, fmt.Errorf("validating positioning atx: %w", err)
+		return nil, fmt.Errorf("%w: validating positioning atx: %w", pubsub.ErrValidationReject, err)
 	}
 
 	marrying, err := h.validateMarriages(watx)
 	if err != nil {
-		return nil, fmt.Errorf("validating marriages: %w", err)
+		return nil, fmt.Errorf("%w: validating marriages: %w", pubsub.ErrValidationReject, err)
 	}
 
 	parts, proof, err := h.syntacticallyValidateDeps(ctx, watx)
 	if err != nil {
-		return nil, fmt.Errorf("atx %s syntactically invalid based on deps: %w", watx.ID(), err)
+		return nil, fmt.Errorf("%w: validating atx %s (deps): %w", pubsub.ErrValidationReject, watx.ID(), err)
 	}
 
 	if proof != nil {
diff --git a/activation/handler_v2_test.go b/activation/handler_v2_test.go
index 3de4a113eb..f4679158a4 100644
--- a/activation/handler_v2_test.go
+++ b/activation/handler_v2_test.go
@@ -18,7 +18,9 @@ import (
 	"github.com/spacemeshos/go-spacemesh/codec"
 	"github.com/spacemeshos/go-spacemesh/common/types"
 	"github.com/spacemeshos/go-spacemesh/datastore"
+	"github.com/spacemeshos/go-spacemesh/fetch"
 	mwire "github.com/spacemeshos/go-spacemesh/malfeasance/wire"
+	"github.com/spacemeshos/go-spacemesh/p2p/pubsub"
 	"github.com/spacemeshos/go-spacemesh/signing"
 	"github.com/spacemeshos/go-spacemesh/sql"
 	"github.com/spacemeshos/go-spacemesh/sql/atxs"
@@ -539,6 +541,7 @@ func TestHandlerV2_ProcessSoloATX(t *testing.T) {
 
 		_, err = atxHandler.processATX(context.Background(), peer, atx, codec.MustEncode(atx), time.Now())
 		require.ErrorContains(t, err, "vrf nonce is not valid")
+		require.ErrorIs(t, err, pubsub.ErrValidationReject)
 
 		_, err = atxs.Get(atxHandler.cdb, atx.ID())
 		require.ErrorIs(t, err, sql.ErrNotFound)
@@ -581,6 +584,7 @@ func TestHandlerV2_ProcessSoloATX(t *testing.T) {
 		atxHandler.expectFetchDeps(atx)
 		_, err := atxHandler.processATX(context.Background(), peer, atx, codec.MustEncode(atx), time.Now())
 		require.ErrorContains(t, err, "validating positioning atx")
+		require.ErrorIs(t, err, pubsub.ErrValidationReject)
 
 		_, err = atxs.Get(atxHandler.cdb, atx.ID())
 		require.ErrorIs(t, err, sql.ErrNotFound)
@@ -706,6 +710,20 @@ func TestHandlerV2_FetchesReferences(t *testing.T) {
 		atxHdlr.mockFetch.EXPECT().GetPoetProof(gomock.Any(), poets[1]).Return(errors.New("pooh"))
 		require.Error(t, atxHdlr.fetchReferences(context.Background(), poets, nil))
 	})
+	t.Run("reject ATX when dependency poet proof is rejected", func(t *testing.T) {
+		t.Parallel()
+		atxHdlr := newV2TestHandler(t, golden)
+
+		poets := []types.Hash32{types.RandomHash()}
+		atxs := []types.ATXID{types.RandomATXID()}
+		var batchErr fetch.BatchError
+		batchErr.Add(atxs[0].Hash32(), pubsub.ErrValidationReject)
+
+		atxHdlr.mockFetch.EXPECT().GetPoetProof(gomock.Any(), poets[0]).Return(&batchErr)
+		atxHdlr.mockFetch.EXPECT().GetAtxs(gomock.Any(), atxs, gomock.Any())
+
+		require.ErrorIs(t, atxHdlr.fetchReferences(context.Background(), poets, atxs), pubsub.ErrValidationReject)
+	})
 
 	t.Run("failed to fetch atxs", func(t *testing.T) {
 		t.Parallel()
@@ -719,6 +737,20 @@ func TestHandlerV2_FetchesReferences(t *testing.T) {
 		atxHdlr.mockFetch.EXPECT().GetAtxs(gomock.Any(), atxs, gomock.Any()).Return(errors.New("oh"))
 		require.Error(t, atxHdlr.fetchReferences(context.Background(), poets, atxs))
 	})
+	t.Run("reject ATX when dependency ATX is rejected", func(t *testing.T) {
+		t.Parallel()
+		atxHdlr := newV2TestHandler(t, golden)
+
+		poets := []types.Hash32{types.RandomHash()}
+		atxs := []types.ATXID{types.RandomATXID(), types.RandomATXID()}
+		var batchErr fetch.BatchError
+		batchErr.Add(atxs[0].Hash32(), pubsub.ErrValidationReject)
+
+		atxHdlr.mockFetch.EXPECT().GetPoetProof(gomock.Any(), poets[0])
+		atxHdlr.mockFetch.EXPECT().GetAtxs(gomock.Any(), atxs, gomock.Any()).Return(&batchErr)
+
+		require.ErrorIs(t, atxHdlr.fetchReferences(context.Background(), poets, atxs), pubsub.ErrValidationReject)
+	})
 	t.Run("no atxs to fetch", func(t *testing.T) {
 		t.Parallel()
 		atxHdlr := newV2TestHandler(t, golden)
@@ -1215,6 +1247,7 @@ func Test_Marriages(t *testing.T) {
 		atxHandler.mclock.EXPECT().CurrentLayer().AnyTimes()
 		_, err = atxHandler.processATX(context.Background(), "", atx, codec.MustEncode(atx), time.Now())
 		require.ErrorContains(t, err, "signer must marry itself")
+		require.ErrorIs(t, err, pubsub.ErrValidationReject)
 	})
 }
 
diff --git a/activation/poet.go b/activation/poet.go
index 174e3b66c1..c16cf1b481 100644
--- a/activation/poet.go
+++ b/activation/poet.go
@@ -21,6 +21,7 @@ import (
 	"github.com/spacemeshos/go-spacemesh/activation/metrics"
 	"github.com/spacemeshos/go-spacemesh/common/types"
 	"github.com/spacemeshos/go-spacemesh/log"
+	"github.com/spacemeshos/go-spacemesh/sql"
 	"github.com/spacemeshos/go-spacemesh/sql/localsql/certifier"
 )
 
@@ -518,7 +519,7 @@ func (c *poetService) Proof(ctx context.Context, roundID string) (*types.PoetPro
 		return nil, nil, fmt.Errorf("getting proof: %w", err)
 	}
 
-	if err := c.db.ValidateAndStore(ctx, proof); err != nil && !errors.Is(err, ErrObjectExists) {
+	if err := c.db.ValidateAndStore(ctx, proof); err != nil && !errors.Is(err, sql.ErrObjectExists) {
 		c.logger.Warn("failed to validate and store proof", zap.Error(err), zap.Object("proof", proof))
 		return nil, nil, fmt.Errorf("validating and storing proof: %w", err)
 	}
diff --git a/activation/poetdb.go b/activation/poetdb.go
index a82cda5e28..39650a1e72 100644
--- a/activation/poetdb.go
+++ b/activation/poetdb.go
@@ -19,8 +19,6 @@ import (
 	"github.com/spacemeshos/go-spacemesh/sql/poets"
 )
 
-var ErrObjectExists = sql.ErrObjectExists
-
 // PoetDb is a database for PoET proofs.
 type PoetDb struct {
 	sqlDB  *sql.Database
diff --git a/fetch/mesh_data.go b/fetch/mesh_data.go
index cf9aedbd3a..37a337ec90 100644
--- a/fetch/mesh_data.go
+++ b/fetch/mesh_data.go
@@ -11,7 +11,6 @@ import (
 	"github.com/spacemeshos/go-scale"
 	"golang.org/x/sync/errgroup"
 
-	"github.com/spacemeshos/go-spacemesh/activation"
 	"github.com/spacemeshos/go-spacemesh/codec"
 	"github.com/spacemeshos/go-spacemesh/common/types"
 	"github.com/spacemeshos/go-spacemesh/datastore"
@@ -19,6 +18,7 @@ import (
 	"github.com/spacemeshos/go-spacemesh/p2p"
 	"github.com/spacemeshos/go-spacemesh/p2p/pubsub"
 	"github.com/spacemeshos/go-spacemesh/p2p/server"
+	"github.com/spacemeshos/go-spacemesh/sql"
 	"github.com/spacemeshos/go-spacemesh/system"
 )
 
@@ -211,7 +211,7 @@ func (f *Fetch) GetPoetProof(ctx context.Context, id types.Hash32) error {
 	switch {
 	case pm.err == nil:
 		return nil
-	case errors.Is(pm.err, activation.ErrObjectExists):
+	case errors.Is(pm.err, sql.ErrObjectExists):
 		// PoET proofs are concurrently stored in DB in two places:
 		// fetcher and nipost builder. Hence, it might happen that
 		// a proof had been inserted into the DB while the fetcher
@@ -400,6 +400,15 @@ func (b *BatchError) Empty() bool {
 	return len(b.Errors) == 0
 }
 
+func (b *BatchError) Is(target error) bool {
+	for _, err := range b.Errors {
+		if errors.Is(err, target) {
+			return true
+		}
+	}
+	return false
+}
+
 func (b *BatchError) Add(id types.Hash32, err error) {
 	if b.Errors == nil {
 		b.Errors = map[types.Hash32]error{}