I've isolated the HEADER frames [1] and locally replicated Netty's decoding errors:
DefaultHttp2Headers[:method: POST, :scheme: https, :authority: kinesis.us-west-2.amazonaws.com, :path: /, amz-sdk-invocation-id: 792fc679-6a8f-5de3-3298-ab18e2e027cc, amz-sdk-retry: 0/0/500, authorization: AWS4-HMAC-SHA256 Credential=AKIAUC4ZWHWB32NVYFHF/20191212/us-west-2/kinesis/aws4_request, SignedHeaders=amz-sdk-invocation-id;amz-sdk-retry;content-length;content-type;host;x-amz-date;x-amz-target, Signature=1e97e0c244c7aee322ac984b0adb822d223c1acf4e8e14834a74581ab9348a42, content-length: 70, content-type: application/x-amz-cbor-1.1, user-agent: aws-sdk-java/2.10.33-SNAPSHOT Mac_OS_X/10.14.6 OpenJDK_64-Bit_Server_VM/25.232-b09 Java/1.8.0_232 vendor/Amazon.com_Inc. io/async http/UNKNOWN, x-amz-date: 20191212T193040Z, x-amz-target: Kinesis_20131202.CreateStream] DefaultHttp2Headers[:method: POST, :scheme: https, :authority: kinesis.us-west-2.amazonaws.com, :path: /, amz-sdk-invocation-id: b24f09bf-31eb-8ccb-57c6-ab66cdbdf09a, amz-sdk-retry: 0/0/500, authorization: AWS4-HMAC-SHA256 Credential=AKIAUC4ZWHWB32NVYFHF/20191212/us-west-2/kinesis/aws4_request, SignedHeaders=amz-sdk-invocation-id;amz-sdk-retry;content-length;content-type;host;x-amz-date;x-amz-target, Signature=6dcaa4c2cffa2ec071b2a7973554d6eb04086486688ede2198f0fa38cfbf9717, content-length: 58, content-type: application/x-amz-cbor-1.1, user-agent: aws-sdk-java/2.10.33-SNAPSHOT Mac_OS_X/10.14.6 OpenJDK_64-Bit_Server_VM/25.232-b09 Java/1.8.0_232 vendor/Amazon.com_Inc. io/async http/UNKNOWN, x-amz-date: 20191212T193040Z, x-amz-target: Kinesis_20131202.DescribeStream] DefaultHttp2Headers[:method: POST, :scheme: https, :authority: kinesis.us-west-2.amazonaws.com, :path: /, amz-sdk-invocation-id: d7411006-3b55-f550-e5f4-7365ca70165a, amz-sdk-retry: 0/0/500, authorization: AWS4-HMAC-SHA256 Credential=AKIAUC4ZWHWB32NVYFHF/20191212/us-west-2/kinesis/aws4_request, SignedHeaders=amz-sdk-invocation-id;amz-sdk-retry;content-length;content-type;host;x-amz-date;x-amz-target, Signature=08a21f6e70a34cd5b9d95ded23176935d3a8c9fe4fd152bee53bcdbd311b202d, content-length: 58, content-type: application/x-amz-cbor-1.1, user-agent: aws-sdk-java/2.10.33-SNAPSHOT Mac_OS_X/10.14.6 OpenJDK_64-Bit_Server_VM/25.232-b09 Java/1.8.0_232 vendor/Amazon.com_Inc. io/async http/UNKNOWN, x-amz-date: 20191212T193041Z, x-amz-target: Kinesis_20131202.DescribeStream] DefaultHttp2Headers[:method: POST, :scheme: https, :authority: kinesis.us-west-2.amazonaws.com, :path: /, amz-sdk-invocation-id: a8ddf801-4f17-70ac-6823-28a5ef4957b0, amz-sdk-retry: 0/0/500, authorization: AWS4-HMAC-SHA256 Credential=AKIAUC4ZWHWB32NVYFHF/20191212/us-west-2/kinesis/aws4_request, SignedHeaders=amz-sdk-invocation-id;amz-sdk-retry;content-length;content-type;host;x-amz-date;x-amz-target, Signature=84cd056300cf959ac460e13cbd3573e54a5859b595b50376f3ca8fbc482a3268, content-length: 58, content-type: application/x-amz-cbor-1.1, user-agent: aws-sdk-java/2.10.33-SNAPSHOT Mac_OS_X/10.14.6 OpenJDK_64-Bit_Server_VM/25.232-b09 Java/1.8.0_232 vendor/Amazon.com_Inc. io/async http/UNKNOWN, x-amz-date: 20191212T193042Z, x-amz-target: Kinesis_20131202.DescribeStream] DefaultHttp2Headers[:method: POST, :scheme: https, :authority: kinesis.us-west-2.amazonaws.com, :path: /, amz-sdk-invocation-id: 633bc940-269a-764a-dd8c-af209c7414aa, amz-sdk-retry: 0/0/500, authorization: AWS4-HMAC-SHA256 Credential=AKIAUC4ZWHWB32NVYFHF/20191212/us-west-2/kinesis/aws4_request, SignedHeaders=amz-sdk-invocation-id;amz-sdk-retry;content-length;content-type;host;x-amz-date;x-amz-target, Signature=5b3f7f46a9e24001cec0191e59713af31179d188197e95cbdce71c949c8483e7, content-length: 58, content-type: application/x-amz-cbor-1.1, user-agent: aws-sdk-java/2.10.33-SNAPSHOT Mac_OS_X/10.14.6 OpenJDK_64-Bit_Server_VM/25.232-b09 Java/1.8.0_232 vendor/Amazon.com_Inc. io/async http/UNKNOWN, x-amz-date: 20191212T193044Z, x-amz-target: Kinesis_20131202.DescribeStream] DefaultHttp2Headers[:method: POST, :scheme: https, :authority: kinesis.us-west-2.amazonaws.com, :path: /, amz-sdk-invocation-id: 10f9569b-ea3f-8724-0361-877feae5520c, amz-sdk-retry: 0/0/500, authorization: AWS4-HMAC-SHA256 Credential=AKIAUC4ZWHWB32NVYFHF/20191212/us-west-2/kinesis/aws4_request, SignedHeaders=amz-sdk-invocation-id;amz-sdk-retry;content-length;content-type;host;x-amz-date;x-amz-target, Signature=de60626e48982123438a40528b8bdd4015e67eda456a844ae27581c62b518e7e, content-length: 58, content-type: application/x-amz-cbor-1.1, user-agent: aws-sdk-java/2.10.33-SNAPSHOT Mac_OS_X/10.14.6 OpenJDK_64-Bit_Server_VM/25.232-b09 Java/1.8.0_232 vendor/Amazon.com_Inc. io/async http/UNKNOWN, x-amz-date: 20191212T193048Z, x-amz-target: Kinesis_20131202.DescribeStream] DefaultHttp2Headers[:method: POST, :scheme: https, :authority: kinesis.us-west-2.amazonaws.com, :path: /, amz-sdk-invocation-id: e6246c99-f2ec-4e43-1903-b985dd3acee1, amz-sdk-retry: 0/0/500, authorization: AWS4-HMAC-SHA256 Credential=AKIAUC4ZWHWB32NVYFHF/20191212/us-west-2/kinesis/aws4_request, SignedHeaders=amz-sdk-invocation-id;amz-sdk-retry;content-length;content-type;host;x-amz-date;x-amz-target, Signature=e75b78e0c30f924d697bb4c0983864abd62edca8838146c6732469d53d10abb2, content-length: 58, content-type: application/x-amz-cbor-1.1, user-agent: aws-sdk-java/2.10.33-SNAPSHOT Mac_OS_X/10.14.6 OpenJDK_64-Bit_Server_VM/25.232-b09 Java/1.8.0_232 vendor/Amazon.com_Inc. io/async http/UNKNOWN, x-amz-date: 20191212T193048Z, x-amz-target: Kinesis_20131202.DescribeStream] DefaultHttp2Headers[:method: POST, :scheme: https, :authority: kinesis.us-west-2.amazonaws.com, :path: /, amz-sdk-invocation-id: d54729d3-6846-2c69-aeca-bb4a1bbc730d, amz-sdk-retry: 0/0/500, authorization: AWS4-HMAC-SHA256 Credential=AKIAUC4ZWHWB32NVYFHF/20191212/us-west-2/kinesis/aws4_request, SignedHeaders=amz-sdk-invocation-id;amz-sdk-retry;content-length;content-type;host;x-amz-date;x-amz-target, Signature=52c91f575c7c6266a1e8053e8be988970e0c475a4ce1f3d3aa0cb62f7a75d6e8, content-length: 58, content-type: application/x-amz-cbor-1.1, user-agent: aws-sdk-java/2.10.33-SNAPSHOT Mac_OS_X/10.14.6 OpenJDK_64-Bit_Server_VM/25.232-b09 Java/1.8.0_232 vendor/Amazon.com_Inc. io/async http/UNKNOWN, x-amz-date: 20191212T193048Z, x-amz-target: Kinesis_20131202.ListShards] io.netty.handler.codec.http2.Http2Exception: HPACK - illegal index value at io.netty.handler.codec.http2.HpackDecoder.indexHeader(..)(Unknown Source) [1] https://gist.githubusercontent.com/rschmitt/36afbc5c0f8117b6c1bfc0bb0d293f70/raw/05c9b56f0f03e166176f0371cee2e79afb70163c/invalid-header-base64.txt
