diff --git a/http2/adapter/callback_visitor.cc b/http2/adapter/callback_visitor.cc
index 981180e..358bfea 100644
--- a/http2/adapter/callback_visitor.cc
+++ b/http2/adapter/callback_visitor.cc
@@ -68,10 +68,8 @@
   QUICHE_LOG(ERROR) << "OnConnectionError not implemented";
 }
 
-void CallbackVisitor::OnFrameHeader(Http2StreamId stream_id,
-                                    size_t length,
-                                    uint8_t type,
-                                    uint8_t flags) {
+bool CallbackVisitor::OnFrameHeader(Http2StreamId stream_id, size_t length,
+                                    uint8_t type, uint8_t flags) {
   QUICHE_VLOG(1) << "CallbackVisitor::OnFrameHeader(stream_id: " << stream_id
                  << ", len: " << length << ", type: " << int(type)
                  << ", flags: " << int(flags) << ")";
@@ -89,9 +87,11 @@
     hd.type = type;
     hd.flags = flags;
     if (callbacks_->on_begin_frame_callback) {
-      callbacks_->on_begin_frame_callback(nullptr, &hd, user_data_);
+      const int result =
+          callbacks_->on_begin_frame_callback(nullptr, &hd, user_data_);
+      return result == 0;
     }
-    return;
+    return true;
   }
   // The general strategy is to clear |current_frame_| at the start of a new
   // frame, accumulate frame information from the various callback events, then
@@ -102,9 +102,11 @@
   current_frame_.hd.type = type;
   current_frame_.hd.flags = flags;
   if (callbacks_->on_begin_frame_callback) {
-    callbacks_->on_begin_frame_callback(nullptr, &current_frame_.hd,
-                                        user_data_);
+    const int result = callbacks_->on_begin_frame_callback(
+        nullptr, &current_frame_.hd, user_data_);
+    return result == 0;
   }
+  return true;
 }
 
 void CallbackVisitor::OnSettingsStart() {}
diff --git a/http2/adapter/callback_visitor.h b/http2/adapter/callback_visitor.h
index 6a15f0a..eb2e2b4 100644
--- a/http2/adapter/callback_visitor.h
+++ b/http2/adapter/callback_visitor.h
@@ -24,9 +24,7 @@
 
   int64_t OnReadyToSend(absl::string_view serialized) override;
   void OnConnectionError() override;
-  void OnFrameHeader(Http2StreamId stream_id,
-                     size_t length,
-                     uint8_t type,
+  bool OnFrameHeader(Http2StreamId stream_id, size_t length, uint8_t type,
                      uint8_t flags) override;
   void OnSettingsStart() override;
   void OnSetting(Http2Setting setting) override;
diff --git a/http2/adapter/http2_visitor_interface.h b/http2/adapter/http2_visitor_interface.h
index 535b174..e04e58c 100644
--- a/http2/adapter/http2_visitor_interface.h
+++ b/http2/adapter/http2_visitor_interface.h
@@ -62,8 +62,10 @@
   virtual void OnConnectionError() = 0;
 
   // Called when the header for a frame is received.
-  virtual void OnFrameHeader(Http2StreamId /*stream_id*/, size_t /*length*/,
-                             uint8_t /*type*/, uint8_t /*flags*/) {}
+  virtual bool OnFrameHeader(Http2StreamId /*stream_id*/, size_t /*length*/,
+                             uint8_t /*type*/, uint8_t /*flags*/) {
+    return true;
+  }
 
   // Called when a non-ack SETTINGS frame is received.
   virtual void OnSettingsStart() = 0;
diff --git a/http2/adapter/mock_http2_visitor.h b/http2/adapter/mock_http2_visitor.h
index 2ca83a4..5498c02 100644
--- a/http2/adapter/mock_http2_visitor.h
+++ b/http2/adapter/mock_http2_visitor.h
@@ -15,6 +15,7 @@
 class QUICHE_NO_EXPORT MockHttp2Visitor : public Http2VisitorInterface {
  public:
   MockHttp2Visitor() {
+    ON_CALL(*this, OnFrameHeader).WillByDefault(testing::Return(true));
     ON_CALL(*this, OnBeginHeadersForStream)
         .WillByDefault(testing::Return(true));
     ON_CALL(*this, OnHeaderForStream).WillByDefault(testing::Return(HEADER_OK));
@@ -27,11 +28,10 @@
   MOCK_METHOD(int64_t, OnReadyToSend, (absl::string_view serialized),
               (override));
   MOCK_METHOD(void, OnConnectionError, (), (override));
-  MOCK_METHOD(
-      void,
-      OnFrameHeader,
-      (Http2StreamId stream_id, size_t length, uint8_t type, uint8_t flags),
-      (override));
+  MOCK_METHOD(bool, OnFrameHeader,
+              (Http2StreamId stream_id, size_t length, uint8_t type,
+               uint8_t flags),
+              (override));
   MOCK_METHOD(void, OnSettingsStart, (), (override));
   MOCK_METHOD(void, OnSetting, (Http2Setting setting), (override));
   MOCK_METHOD(void, OnSettingsEnd, (), (override));
diff --git a/http2/adapter/nghttp2_adapter_test.cc b/http2/adapter/nghttp2_adapter_test.cc
index ad66439..bc81936 100644
--- a/http2/adapter/nghttp2_adapter_test.cc
+++ b/http2/adapter/nghttp2_adapter_test.cc
@@ -1428,6 +1428,51 @@
   EXPECT_THAT(visitor.data(), EqualsFrames({spdy::SpdyFrameType::SETTINGS}));
 }
 
+// Exercises the case when a visitor chooses to reject a frame based solely on
+// the frame header, which is a fatal error for the connection.
+TEST(NgHttp2AdapterTest, ServerRejectsFrameHeader) {
+  DataSavingVisitor visitor;
+  auto adapter = NgHttp2Adapter::CreateServerAdapter(visitor);
+
+  const std::string frames = TestFrameSequence()
+                                 .ClientPreface()
+                                 .Ping(64)
+                                 .Headers(1,
+                                          {{":method", "POST"},
+                                           {":scheme", "https"},
+                                           {":authority", "example.com"},
+                                           {":path", "/this/is/request/one"}},
+                                          /*fin=*/false)
+                                 .WindowUpdate(1, 2000)
+                                 .Data(1, "This is the request body.")
+                                 .WindowUpdate(0, 2000)
+                                 .Serialize();
+  testing::InSequence s;
+
+  // Client preface (empty SETTINGS)
+  EXPECT_CALL(visitor, OnFrameHeader(0, 0, SETTINGS, 0));
+  EXPECT_CALL(visitor, OnSettingsStart());
+  EXPECT_CALL(visitor, OnSettingsEnd());
+
+  EXPECT_CALL(visitor, OnFrameHeader(0, 8, PING, 0))
+      .WillOnce(testing::Return(false));
+  EXPECT_CALL(visitor, OnConnectionError());
+
+  const int64_t result = adapter->ProcessBytes(frames);
+  EXPECT_EQ(-902, result);
+
+  EXPECT_TRUE(adapter->session().want_write());
+
+  EXPECT_CALL(visitor, OnBeforeFrameSent(SETTINGS, 0, 0, 0x1));
+  EXPECT_CALL(visitor, OnFrameSent(SETTINGS, 0, 0, 0x1, 0));
+
+  int send_result = adapter->Send();
+  // Some bytes should have been serialized.
+  EXPECT_EQ(0, send_result);
+  // SETTINGS ack
+  EXPECT_THAT(visitor.data(), EqualsFrames({spdy::SpdyFrameType::SETTINGS}));
+}
+
 TEST(NgHttp2AdapterTest, ServerSubmitResponse) {
   DataSavingVisitor visitor;
   auto adapter = NgHttp2Adapter::CreateServerAdapter(visitor);
diff --git a/http2/adapter/nghttp2_callbacks.cc b/http2/adapter/nghttp2_callbacks.cc
index e22d437..17fb1a0 100644
--- a/http2/adapter/nghttp2_callbacks.cc
+++ b/http2/adapter/nghttp2_callbacks.cc
@@ -39,8 +39,11 @@
                  void* user_data) {
   QUICHE_CHECK_NE(user_data, nullptr);
   auto* visitor = static_cast<Http2VisitorInterface*>(user_data);
-  visitor->OnFrameHeader(header->stream_id, header->length, header->type,
-                         header->flags);
+  bool result = visitor->OnFrameHeader(header->stream_id, header->length,
+                                       header->type, header->flags);
+  if (!result) {
+    return NGHTTP2_ERR_CALLBACK_FAILURE;
+  }
   if (header->type == NGHTTP2_DATA) {
     visitor->OnBeginDataForStream(header->stream_id, header->length);
   } else if (header->type == kMetadataFrameType) {
diff --git a/http2/adapter/oghttp2_adapter_test.cc b/http2/adapter/oghttp2_adapter_test.cc
index 75f6121..4cffe2e 100644
--- a/http2/adapter/oghttp2_adapter_test.cc
+++ b/http2/adapter/oghttp2_adapter_test.cc
@@ -1063,6 +1063,56 @@
                                             spdy::SpdyFrameType::SETTINGS}));
 }
 
+// Exercises the case when a visitor chooses to reject a frame based solely on
+// the frame header, which is a fatal error for the connection.
+TEST(OgHttp2AdapterServerTest, ServerRejectsFrameHeader) {
+  DataSavingVisitor visitor;
+  OgHttp2Adapter::Options options{.perspective = Perspective::kServer};
+  auto adapter = OgHttp2Adapter::Create(visitor, options);
+
+  const std::string frames = TestFrameSequence()
+                                 .ClientPreface()
+                                 .Ping(64)
+                                 .Headers(1,
+                                          {{":method", "POST"},
+                                           {":scheme", "https"},
+                                           {":authority", "example.com"},
+                                           {":path", "/this/is/request/one"}},
+                                          /*fin=*/false)
+                                 .WindowUpdate(1, 2000)
+                                 .Data(1, "This is the request body.")
+                                 .WindowUpdate(0, 2000)
+                                 .Serialize();
+  testing::InSequence s;
+
+  // Client preface (empty SETTINGS)
+  EXPECT_CALL(visitor, OnFrameHeader(0, 0, SETTINGS, 0));
+  EXPECT_CALL(visitor, OnSettingsStart());
+  EXPECT_CALL(visitor, OnSettingsEnd());
+
+  EXPECT_CALL(visitor, OnFrameHeader(0, 8, PING, 0))
+      .WillOnce(testing::Return(false));
+  EXPECT_CALL(visitor, OnConnectionError());
+
+  const int64_t result = adapter->ProcessBytes(frames);
+  EXPECT_GT(result, 0);
+  EXPECT_LT(result, static_cast<int64_t>(frames.size()));
+
+  EXPECT_TRUE(adapter->session().want_write());
+
+  EXPECT_CALL(visitor, OnBeforeFrameSent(SETTINGS, 0, 0, 0x0));
+  EXPECT_CALL(visitor, OnFrameSent(SETTINGS, 0, 0, 0x0, 0));
+  EXPECT_CALL(visitor, OnBeforeFrameSent(SETTINGS, 0, 0, 0x1));
+  EXPECT_CALL(visitor, OnFrameSent(SETTINGS, 0, 0, 0x1, 0));
+
+  int send_result = adapter->Send();
+  // Some bytes should have been serialized.
+  EXPECT_EQ(0, send_result);
+  // SETTINGS and SETTINGS ack
+  EXPECT_THAT(visitor.data(), EqualsFrames({spdy::SpdyFrameType::SETTINGS,
+                                            spdy::SpdyFrameType::SETTINGS}));
+}
+
 }  // namespace
 }  // namespace test
 }  // namespace adapter
diff --git a/http2/adapter/oghttp2_session.cc b/http2/adapter/oghttp2_session.cc
index b3505b8..39703a4 100644
--- a/http2/adapter/oghttp2_session.cc
+++ b/http2/adapter/oghttp2_session.cc
@@ -585,7 +585,10 @@
                                     uint8_t flags) {
   highest_received_stream_id_ = std::max(static_cast<Http2StreamId>(stream_id),
                                          highest_received_stream_id_);
-  visitor_.OnFrameHeader(stream_id, length, type, flags);
+  const bool result = visitor_.OnFrameHeader(stream_id, length, type, flags);
+  if (!result) {
+    decoder_.StopProcessing();
+  }
 }
 
 void OgHttp2Session::OnDataFrameHeader(spdy::SpdyStreamId stream_id,
diff --git a/http2/adapter/recording_http2_visitor.cc b/http2/adapter/recording_http2_visitor.cc
index b66d5e0..767f3a7 100644
--- a/http2/adapter/recording_http2_visitor.cc
+++ b/http2/adapter/recording_http2_visitor.cc
@@ -16,12 +16,12 @@
   events_.push_back("OnConnectionError");
 }
 
-void RecordingHttp2Visitor::OnFrameHeader(Http2StreamId stream_id,
-                                          size_t length,
-                                          uint8_t type,
+bool RecordingHttp2Visitor::OnFrameHeader(Http2StreamId stream_id,
+                                          size_t length, uint8_t type,
                                           uint8_t flags) {
   events_.push_back(absl::StrFormat("OnFrameHeader %d %d %d %d", stream_id,
                                     length, type, flags));
+  return true;
 }
 
 void RecordingHttp2Visitor::OnSettingsStart() {
diff --git a/http2/adapter/recording_http2_visitor.h b/http2/adapter/recording_http2_visitor.h
index 9627445..ee06b1e 100644
--- a/http2/adapter/recording_http2_visitor.h
+++ b/http2/adapter/recording_http2_visitor.h
@@ -22,9 +22,7 @@
   // From Http2VisitorInterface
   int64_t OnReadyToSend(absl::string_view serialized) override;
   void OnConnectionError() override;
-  void OnFrameHeader(Http2StreamId stream_id,
-                     size_t length,
-                     uint8_t type,
+  bool OnFrameHeader(Http2StreamId stream_id, size_t length, uint8_t type,
                      uint8_t flags) override;
   void OnSettingsStart() override;
   void OnSetting(Http2Setting setting) override;