diff --git a/quiche/http2/adapter/http2_util.cc b/quiche/http2/adapter/http2_util.cc
index 7cca26b..963d264 100644
--- a/quiche/http2/adapter/http2_util.cc
+++ b/quiche/http2/adapter/http2_util.cc
@@ -99,6 +99,8 @@
       return "ExceededMaxConcurrentStreams";
     case ConnectionError::kFlowControlError:
       return "FlowControlError";
+    case ConnectionError::kInvalidGoAwayLastStreamId:
+      return "InvalidGoAwayLastStreamId";
   }
   return "UnknownConnectionError";
 }
diff --git a/quiche/http2/adapter/http2_visitor_interface.h b/quiche/http2/adapter/http2_visitor_interface.h
index 012d91a..2ec68c5 100644
--- a/quiche/http2/adapter/http2_visitor_interface.h
+++ b/quiche/http2/adapter/http2_visitor_interface.h
@@ -80,6 +80,8 @@
     kExceededMaxConcurrentStreams,
     // The peer caused a flow control error.
     kFlowControlError,
+    // The peer sent a GOAWAY with an invalid last-stream-ID field.
+    kInvalidGoAwayLastStreamId,
   };
   virtual void OnConnectionError(ConnectionError error) = 0;
 
diff --git a/quiche/http2/adapter/nghttp2_adapter_test.cc b/quiche/http2/adapter/nghttp2_adapter_test.cc
index 4c1c4ec..f542429 100644
--- a/quiche/http2/adapter/nghttp2_adapter_test.cc
+++ b/quiche/http2/adapter/nghttp2_adapter_test.cc
@@ -1702,6 +1702,67 @@
   EXPECT_THAT(visitor.data(), testing::IsEmpty());
 }
 
+TEST(NgHttp2AdapterTest, ClientReceivesMultipleGoAwaysWithIncreasingStreamId) {
+  DataSavingVisitor visitor;
+  auto adapter = NgHttp2Adapter::CreateClientAdapter(visitor);
+
+  testing::InSequence s;
+
+  const std::vector<Header> headers1 =
+      ToHeaders({{":method", "GET"},
+                 {":scheme", "http"},
+                 {":authority", "example.com"},
+                 {":path", "/this/is/request/one"}});
+
+  const int32_t stream_id1 = adapter->SubmitRequest(headers1, nullptr, nullptr);
+  ASSERT_GT(stream_id1, 0);
+
+  EXPECT_CALL(visitor, OnBeforeFrameSent(HEADERS, stream_id1, _, 0x5));
+  EXPECT_CALL(visitor, OnFrameSent(HEADERS, stream_id1, _, 0x5, 0));
+
+  int result = adapter->Send();
+  EXPECT_EQ(0, result);
+  absl::string_view data = visitor.data();
+  EXPECT_THAT(data, testing::StartsWith(spdy::kHttp2ConnectionHeaderPrefix));
+  data.remove_prefix(strlen(spdy::kHttp2ConnectionHeaderPrefix));
+  EXPECT_THAT(data, EqualsFrames({SpdyFrameType::HEADERS}));
+  visitor.Clear();
+
+  const std::string frames =
+      TestFrameSequence()
+          .ServerPreface()
+          .GoAway(0, Http2ErrorCode::HTTP2_NO_ERROR, "")
+          .GoAway(0, Http2ErrorCode::ENHANCE_YOUR_CALM, "")
+          .GoAway(1, Http2ErrorCode::INTERNAL_ERROR, "")
+          .Serialize();
+
+  EXPECT_CALL(visitor, OnFrameHeader(0, 0, SETTINGS, 0));
+  EXPECT_CALL(visitor, OnSettingsStart());
+  EXPECT_CALL(visitor, OnSettingsEnd());
+  EXPECT_CALL(visitor, OnFrameHeader(0, _, GOAWAY, 0));
+  EXPECT_CALL(visitor, OnGoAway(0, Http2ErrorCode::HTTP2_NO_ERROR, ""));
+  EXPECT_CALL(visitor, OnCloseStream(1, Http2ErrorCode::REFUSED_STREAM));
+  EXPECT_CALL(visitor, OnFrameHeader(0, _, GOAWAY, 0));
+  EXPECT_CALL(visitor, OnGoAway(0, Http2ErrorCode::ENHANCE_YOUR_CALM, ""));
+  EXPECT_CALL(visitor, OnFrameHeader(0, _, GOAWAY, 0));
+  EXPECT_CALL(
+      visitor,
+      OnInvalidFrame(0, Http2VisitorInterface::InvalidFrameError::kProtocol));
+
+  const int64_t frames_result = adapter->ProcessBytes(frames);
+  EXPECT_EQ(frames.size(), static_cast<size_t>(frames_result));
+
+  EXPECT_CALL(visitor, OnBeforeFrameSent(GOAWAY, 0, _, 0x0));
+  EXPECT_CALL(visitor,
+              OnFrameSent(GOAWAY, 0, _, 0x0,
+                          static_cast<int>(Http2ErrorCode::PROTOCOL_ERROR)));
+
+  EXPECT_TRUE(adapter->want_write());
+  result = adapter->Send();
+  EXPECT_EQ(0, result);
+  EXPECT_THAT(visitor.data(), EqualsFrames({SpdyFrameType::GOAWAY}));
+}
+
 TEST(NgHttp2AdapterTest, ClientReceivesGoAwayWithPendingStreams) {
   DataSavingVisitor visitor;
   auto adapter = NgHttp2Adapter::CreateClientAdapter(visitor);
diff --git a/quiche/http2/adapter/oghttp2_adapter_test.cc b/quiche/http2/adapter/oghttp2_adapter_test.cc
index c2ae248..1c178b5 100644
--- a/quiche/http2/adapter/oghttp2_adapter_test.cc
+++ b/quiche/http2/adapter/oghttp2_adapter_test.cc
@@ -2075,6 +2075,74 @@
   EXPECT_THAT(visitor.data(), testing::IsEmpty());
 }
 
+TEST(OgHttp2AdapterTest, ClientReceivesMultipleGoAwaysWithIncreasingStreamId) {
+  DataSavingVisitor visitor;
+  OgHttp2Adapter::Options options{.perspective = Perspective::kClient};
+  auto adapter = OgHttp2Adapter::Create(visitor, options);
+
+  testing::InSequence s;
+
+  const std::vector<Header> headers1 =
+      ToHeaders({{":method", "GET"},
+                 {":scheme", "http"},
+                 {":authority", "example.com"},
+                 {":path", "/this/is/request/one"}});
+
+  const int32_t stream_id1 = adapter->SubmitRequest(headers1, nullptr, nullptr);
+  ASSERT_GT(stream_id1, 0);
+
+  EXPECT_CALL(visitor, OnBeforeFrameSent(SETTINGS, 0, _, 0x0));
+  EXPECT_CALL(visitor, OnFrameSent(SETTINGS, 0, _, 0x0, 0));
+  EXPECT_CALL(visitor, OnBeforeFrameSent(HEADERS, stream_id1, _, 0x5));
+  EXPECT_CALL(visitor, OnFrameSent(HEADERS, stream_id1, _, 0x5, 0));
+
+  int result = adapter->Send();
+  EXPECT_EQ(0, result);
+  absl::string_view data = visitor.data();
+  EXPECT_THAT(data, testing::StartsWith(spdy::kHttp2ConnectionHeaderPrefix));
+  data.remove_prefix(strlen(spdy::kHttp2ConnectionHeaderPrefix));
+  EXPECT_THAT(data,
+              EqualsFrames({SpdyFrameType::SETTINGS, SpdyFrameType::HEADERS}));
+  visitor.Clear();
+
+  const std::string frames =
+      TestFrameSequence()
+          .ServerPreface()
+          .GoAway(0, Http2ErrorCode::HTTP2_NO_ERROR, "")
+          .GoAway(0, Http2ErrorCode::ENHANCE_YOUR_CALM, "")
+          .GoAway(1, Http2ErrorCode::INTERNAL_ERROR, "")
+          .Serialize();
+
+  EXPECT_CALL(visitor, OnFrameHeader(0, 0, SETTINGS, 0));
+  EXPECT_CALL(visitor, OnSettingsStart());
+  EXPECT_CALL(visitor, OnSettingsEnd());
+  EXPECT_CALL(visitor, OnFrameHeader(0, _, GOAWAY, 0));
+  EXPECT_CALL(visitor, OnGoAway(0, Http2ErrorCode::HTTP2_NO_ERROR, ""));
+  EXPECT_CALL(visitor, OnCloseStream(1, Http2ErrorCode::REFUSED_STREAM));
+  EXPECT_CALL(visitor, OnFrameHeader(0, _, GOAWAY, 0));
+  EXPECT_CALL(visitor, OnGoAway(0, Http2ErrorCode::ENHANCE_YOUR_CALM, ""));
+  EXPECT_CALL(visitor, OnFrameHeader(0, _, GOAWAY, 0));
+  EXPECT_CALL(
+      visitor,
+      OnInvalidFrame(0, Http2VisitorInterface::InvalidFrameError::kProtocol));
+  // The oghttp2 stack also signals the error via OnConnectionError().
+  EXPECT_CALL(visitor,
+              OnConnectionError(ConnectionError::kInvalidGoAwayLastStreamId));
+
+  const int64_t frames_result = adapter->ProcessBytes(frames);
+  EXPECT_EQ(frames.size(), static_cast<size_t>(frames_result));
+
+  EXPECT_CALL(visitor, OnBeforeFrameSent(GOAWAY, 0, _, 0x0));
+  EXPECT_CALL(visitor,
+              OnFrameSent(GOAWAY, 0, _, 0x0,
+                          static_cast<int>(Http2ErrorCode::PROTOCOL_ERROR)));
+
+  EXPECT_TRUE(adapter->want_write());
+  result = adapter->Send();
+  EXPECT_EQ(0, result);
+  EXPECT_THAT(visitor.data(), EqualsFrames({SpdyFrameType::GOAWAY}));
+}
+
 TEST(OgHttp2AdapterTest, ClientReceivesGoAwayWithPendingStreams) {
   DataSavingVisitor visitor;
   OgHttp2Adapter::Options options{.perspective = Perspective::kClient};
diff --git a/quiche/http2/adapter/oghttp2_session.cc b/quiche/http2/adapter/oghttp2_session.cc
index 1c84c3e..7d99ab2 100644
--- a/quiche/http2/adapter/oghttp2_session.cc
+++ b/quiche/http2/adapter/oghttp2_session.cc
@@ -1301,8 +1301,23 @@
 
 void OgHttp2Session::OnGoAway(spdy::SpdyStreamId last_accepted_stream_id,
                               spdy::SpdyErrorCode error_code) {
+  if (received_goaway_ &&
+      last_accepted_stream_id >
+          static_cast<spdy::SpdyStreamId>(received_goaway_stream_id_)) {
+    // This GOAWAY has a higher `last_accepted_stream_id` than a previous
+    // GOAWAY, a connection-level spec violation.
+    const bool ok = visitor_.OnInvalidFrame(
+        kConnectionStreamId,
+        Http2VisitorInterface::InvalidFrameError::kProtocol);
+    if (!ok) {
+      fatal_visitor_callback_failure_ = true;
+    }
+    LatchErrorAndNotify(Http2ErrorCode::PROTOCOL_ERROR,
+                        ConnectionError::kInvalidGoAwayLastStreamId);
+    return;
+  }
+
   received_goaway_ = true;
-  // TODO(diannahu): Validate that `last_accepted_stream_id` is non-increasing.
   received_goaway_stream_id_ = last_accepted_stream_id;
   const bool result = visitor_.OnGoAway(last_accepted_stream_id,
                                         TranslateErrorCode(error_code), "");