What's Changed

• SingleThreadEventExecutor: document Throwable safety contract on run() by @daguimu in #16814
• Make HTTP/2 frame hashCode consistent with equals by @daguimu in #16692
• Add BlockHound exception for DnsQueryIdSpace (#16896) by @chrisvest in #16915
• FlowControlHandler: Fix autoRead behavior by @chrisvest in #16912
• Auto-port 4.1: Fix incorrect bounds in error message of HpackDecoder.setMaxHeaderListSize by @netty-project-bot in #16911
• MQTT: Fix MQTT decoder size check after variable header replay by @daguimu in #16916
• MQTT: Make the decodeProperties early-REPLAY check actually fire by @daguimu in #16813
• Reject control characters at the boundary of HTTP method names (#16723) by @chrisvest in #16933
• Auto-port 4.1: Update to latest tcnative release by @netty-project-bot in #16941
• Auto-port 4.1: Fix HTTP 2 PUSH_PROMISE stream association validation by @netty-project-bot in #16955
• Auto-port 4.1: Fix GZIP FEXTRA extra-field handling in JdkZlibDecoder by @netty-project-bot in #16957
• Auto-port 4.1: Add opt-in validation of mandatory pseudo-header fields for HTTP/2 by @netty-project-bot in #16964
• Strictly validate MQTT UTF-8 Encoded String (#16939) by @chrisvest in #16965
• Auto-port 4.1: Stop DateFormatter trailing token from running past the parse end by @netty-project-bot in #16968
• Auto-port 4.1: IpFilter: Deprecate constructor which use accept by default by @netty-project-bot in #16973
• Add RFC 10008 QUERY Method support (#16966) by @normanmaurer in #16978
• Correctly release and fail queued traffic-shaping writes on close (#16959) by @normanmaurer in #16976
• Auto-port 4.1: FlowControlHandler: respect auto-read when toggled while dequeueing by @netty-project-bot in #16983
• IdleStateHandler: reset firstWriter/ReaderIdleEvent in resetWriteTimeout/resetReadTimeout (#16982) by @chrisvest in #16989
• Auto-port 4.1: Fix typo in AbstractSniHandler Javadoc by @netty-project-bot in #16995
• Auto-port 4.1: Reconcile AbstractCoalescingBufferQueue readableBytes when it drains, and fail stuck HTTP/2 streams instead of spinning empty DATA frames by @netty-project-bot in #16997
• Reject control characters at the boundary of the HTTP version token (#16971) by @normanmaurer in #16986
• Auto-port 4.1: Reset UTF-8 decode state on CR in StompSubframeDecoder by @netty-project-bot in #17003
• Auto-port 4.1: HTTP2: Pass the correct number of arguments when logging goaway by @netty-project-bot in #17017
• FastLz: Guard decompression against truncated input (#17000) by @chrisvest in #17015
• Backport 4.1 Fix propagation of startTls for client SslContext handler by @skyguard1 in #17020
• Auto-port 4.1: Reject non-token characters in HTTP/2 header names by @netty-project-bot in #17022
• Update lz4-java to 1.11.1 by @yawkat in #17060
• Pin github actions to reduce risk (#17043) by @normanmaurer in #17044
• Merge branches from forks (#17063) by @normanmaurer in #17065

Full Changelog: netty-4.1.135.Final...netty-4.1.136.Final

What's Changed

• Document Java 9 requirement for io_uring by @jchambers in #16904
• Add BlockHound exception for DnsQueryIdSpace by @violetagg in #16896
• Fix incorrect bounds in error message of HpackDecoder.setMaxHeaderListSize by @skyguard1 in #16901
• Add epoch-based chunk cache purge with ring buffer for thread-local reuse by @franz1981 in #16766
• Use Splittable/ThreadLocalRandom to generate bulk data in tests by @chrisvest in #16808
• Auto-port 4.2: SingleThreadEventExecutor: document Throwable safety contract on run() by @netty-project-bot in #16909
• Auto-port 4.2: Make HTTP/2 frame hashCode consistent with equals by @netty-project-bot in #16910
• Auto-port 4.2: MQTT: Make the decodeProperties early-REPLAY check actually fire by @netty-project-bot in #16919
• IoUring: fix io_uring datagram writes with non-zero readerIndex by @dreamlike-ocean in #16905
• Exclude internal events from IoHandler.run() return value in epoll, io_uring and kqueue by @franz1981 in #16848
• IoUring: Pass IORING_ENTER_NO_IOWAIT to report accurate CPU usage by @wineway in #16739
• Avoid logging exceptions that tests ignore by @chrisvest in #16891
• Reject control characters at the boundary of HTTP method names by @daguimu in #16723
• IoUring: fix TCP Fast Open initial writes with readerIndex and composites by @dreamlike-ocean in #16929
• Try to fix/stabilize a number of flaky tests by @chrisvest in #16934
• Fix propagation of startTls for client SslContext handlers by @skyguard1 in #16931
• Update to latest tcnative release by @normanmaurer in #16936
• Move test to shared testsuite by @normanmaurer in #16928
• [Refactor] Useful helper method getOrDefault & cleaner abstraction by @sanjomo in #16927
• Make permessage-deflate server window size and memLevel configurable by @fru1tworld in #16809
• Return early in DnsQueryContext.writeQuery when the query ID space is exhausted by @HwangRock in #16950
• Fix HTTP 2 PUSH_PROMISE stream association validation by @skyguard1 in #16952
• Fix GZIP FEXTRA extra-field handling in JdkZlibDecoder by @daguimu in #16951
• Http3FrameCodec handle fragmented payloads when skipping unknown frames by @skyguard1 in #16960
• Add opt-in validation of mandatory pseudo-header fields for HTTP/2 by @hyperxpro in #16932
• Strictly validate MQTT UTF-8 Encoded String by @skyguard1 in #16939
• Stop DateFormatter trailing token from running past the parse end by @daguimu in #16958
• IpFilter: Deprecate constructor which use accept by default by @normanmaurer in #16961
• Add RFC 10008 QUERY Method support by @desiderantes in #16966
• Correctly release and fail queued traffic-shaping writes on close by @skyguard1 in #16959
• Reject control characters at the boundary of the HTTP version token by @HwangRock in #16971
• FlowControlHandler: respect auto-read when toggled while dequeueing by @schiemon in #16949
• Fix leak in ReferenceCountedOpenSslEngine.addCredential by @jmcrawford45 in #16979
• IdleStateHandler: reset firstWriter/ReaderIdleEvent in resetWriteTimeout/resetReadTimeout by @husseinvr97 in #16982
• Fix typo in AbstractSniHandler Javadoc by @coderbruis in #16988
• Fix client/server inconsistency in SslCredential support matrix by @jmcrawford45 in #16990
• Reconcile AbstractCoalescingBufferQueue readableBytes when it drains, and fail stuck HTTP/2 streams instead of spinning empty DATA frames by @gavinbunney in #16947
• Use Ticker in Http2MaxRstFrameListener for testability by @skyguard1 in #16993
• Reset UTF-8 decode state on CR in StompSubframeDecoder by @vasiliy-mikhailov in #16991
• FastLz: Guard decompression against truncated input by @yawkat in #17000
• Reject non-token characters in HTTP/2 header names by @daguimu in #16762
• Auto-port 4.2: Fix SelfSignCertificate initialization in tests by @netty-project-bot in #17029
• Enable extension of Http3ClientConnectionHandler to support higher-level protocols such as WebTransport. by @sanjomo in #17027
• Implement Adaptive Cumulator by @shivaspeaks in #16731
• Allow WebSocket extension negotiation to be disabled per response by @mkurz in #17030
• Support QPACK sensitivity detector for Never Indexed header fields by @skyguard1 in #17026
• Fix maxAllocation for brotli-encoded content in HttpContentDecompressor by @skyguard1 in #17037
• Pin github actions to reduce risk by @normanmaurer in #17043
• Update lz4-java to 1.11.1 by @yawkat in #17061
• Merge branches from forks by @chrisvest in #17063

New Contributors

• @HwangRock made their first contribution in #16950
• @desiderantes made their first contribution in #16966
• @husseinvr97 made their first contribution in #16982
• @gavinbunney made their first contribution in #16947
• @vasiliy-mikhailov made their first contribution in #16991
• @shivaspeaks made their first contribution in #16731

Full Changelog: netty-4.2.15.Final...netty-4.2.16.Final

Security fixes

• CVE-2026-48059: memory exhaustion in io.netty:netty-codec-haproxy (high).
• CVE-2026-47691: DNS cache poisoning in io.netty:netty-resolver-dns (high).
• CVE-2026-50560: DDoS in io.netty:netty-codec-http2.
• CVE-2026-50011: memory exhaustion in io.netty:netty-codec-redis (high).
• CVE-2026-44250: memory exhaustion in io.netty:netty-codec-redis (high).
• CVE-2026-44890: memory exhaustion in io.netty:netty-codec-redis (high).
• CVE-2026-50009: information disclosure and denial of service in io.netty:netty-codec-classes-quic.
• CVE-2026-44249: IPv6 subnet filter bypass in io.netty:netty-handler (high).
• CVE-2026-50020: request smuggling in io.netty:netty-codec-http.
• CVE-2026-44892: memory exhaustion in io.netty:netty-codec-http3 (high).
• CVE-2026-44893: memory leak in io.netty:netty-codec-haproxy (high).
• CVE-2026-44894: traffic amplification in io.netty:netty-codec-classes-quic (high).
• CVE-2026-50010: TLS hostname verification accidentally disabled in io.netty:netty-handler (high).
• CVE-2026-45673: DNS cache poisoning in io.netty:netty-resolver-dns.
• CVE-2026-45416: excessive memory usage from SNIHandler in io.netty:netty-handler (high).
• CVE-2026-45536: file descriptor leak in io.netty:netty-transport-native-epoll and io.netty:netty-transport-native-kqueue.
• CVE-2026-45674: DNS cache poisoning in io.netty:netty-resolver-dns (high).
• CVE-2026-46340: memory exhaustion in io.netty:netty-transport-sctp (high).
• CVE-2026-47244: denial of service in io.netty:netty-codec-http2.
• CVE-2026-48006: memory exhaustion in io.netty:netty-codec-redis (high).
• CVE-2026-48748: memory exhaustion in io.netty:netty-codec-http3 (high).
• CVE-2026-48043: memory exhaustion in io.netty:netty-codec-http2.

What's Changed

• Fix race in io.netty.channel.uring.IoUringIoHandler.wakeup by @dreamlike-ocean in #16836
• HTTP/2: Parse request-target path like Vert.x by @yawkat in #16810
• Auto-port 4.2: ChannelInitializer: correct misleading comment on exceptionCaught route by @netty-project-bot in #16853
• FlowControlHandler: Suppress duplicate channelReadComplete after draining queue (#15053) by @schiemon in #16837
• Pass maxAllocation to Brotli and Zstd decoders by @fedinskiy in #16844
• Fix revapi warnings by @chrisvest in #16885
• Fix SCTP and Redis tests by @chrisvest in #16893
• Add maxWindowLog parameter to ZstdDecoder to bound memory allocation by @skyguard1 in #16850
• Auto-port 4.2: MQTT: Reject malformed no-payload packets with non-zero Remaining Length by @netty-project-bot in #16890

New Contributors

• @schiemon made their first contribution in #16837
• @fedinskiy made their first contribution in #16844

Full Changelog: netty-4.2.14.Final...netty-4.2.15.Final

Security fixes

• CVE-2026-48059: memory exhaustion in io.netty:netty-codec-haproxy (high).
• CVE-2026-47691: DNS cache poisoning in io.netty:netty-resolver-dns (high).
• CVE-2026-50560: DDoS in io.netty:netty-codec-http2.
• CVE-2026-50011: memory exhaustion in io.netty:netty-codec-redis (high).
• CVE-2026-44250: memory exhaustion in io.netty:netty-codec-redis (high).
• CVE-2026-44890: memory exhaustion in io.netty:netty-codec-redis (high).
• CVE-2026-44249: IPv6 subnet filter bypass in io.netty:netty-handler (high).
• CVE-2026-50020: request smuggling in io.netty:netty-codec-http.
• CVE-2026-44893: memory leak in io.netty:netty-codec-haproxy (high).
• CVE-2026-50010: TLS hostname verification accidentally disabled in io.netty:netty-handler (high).
• CVE-2026-45673: DNS cache poisoning in io.netty:netty-resolver-dns.
• CVE-2026-45416: excessive memory usage from SNIHandler in io.netty:netty-handler (high).
• CVE-2026-45536: file descriptor leak in io.netty:netty-transport-native-epoll and io.netty:netty-transport-native-kqueue.
• CVE-2026-45674: DNS cache poisoning in io.netty:netty-resolver-dns (high).
• CVE-2026-46340: memory exhaustion in io.netty:netty-transport-sctp (high).
• CVE-2026-47244: denial of service in io.netty:netty-codec-http2.
• CVE-2026-48006: memory exhaustion in io.netty:netty-codec-redis (high).
• CVE-2026-48043: memory exhaustion in io.netty:netty-codec-http2.

What's Changed

• Auto-port 4.1: MQTT: Allow MQTT 5 CONNECT with password only by @netty-project-bot in #16834
• ChannelInitializer: correct misleading comment on exceptionCaught route by @daguimu in #16847
• HTTP/2: Parse request-target path like Vert.x (4.1 backport) by @yawkat in #16856
• HttpObjectDecoder skips arbitrary initial control characters when only initial CRLF characters are permitted by @normanmaurer in #16861
• IpSubnetFilter: Correctly handle ipv6 by @normanmaurer in #16860
• Configurable bound on RedisArrayAggregator by @normanmaurer in #16858
• Redis: Limit decoded length by @normanmaurer in #16859
• DNS: Ensure query id is not predictible by @normanmaurer in #16870
• Wrapping plain trust manager silently disables hostname verification by @normanmaurer in #16868
• MQTT: Reject malformed no-payload packets with non-zero Remaining Length by @daguimu in #16852
• Fix revapi warnings (#16885) by @chrisvest in #16892
• HAProxy: Reject HAProxyMessages with malformated TLV and not leak memory by @normanmaurer in #16866
• SSL: Use sane defaults as limits for the client hello length and timeout by @normanmaurer in #16871
• DNS: Only cache CNAME if part of the queried domain by @normanmaurer in #16873
• HTTP/2: Enforce max concurrent streams for misbehaving clients by @normanmaurer in #16876
• Dns: Insufficient Bailiwick Validation for NS Records by @normanmaurer in #16877
• HTTP2: DelegatingDecompressorFrameListener must release memory in all cases by @normanmaurer in #16880
• Pass maxAllocation to Brotli and Zstd decoders (#16844) by @chrisvest in #16886
• HTTP/2: Treat clients MAX_HEADER_LIST_SIZE as advisory by @normanmaurer in #16883
• Auto-port 4.1: Add maxWindowLog parameter to ZstdDecoder to bound memory allocation by @netty-project-bot in #16894
• HAProxy: Fix ByteBuf leak when parsing nested SSL TLVs by @normanmaurer in #16881
• Epoll / Kqueue: Correctly handle receive of FD by @normanmaurer in #16872
• SCTP: Limit the number of inflight incomplete SCTP messages and the number of fragments by @normanmaurer in #16875
• Redis: Correctly release incomplete message on removal when using RedisArrayAggregator by @normanmaurer in #16878
• Redis: Limit the maximum number of nested arrays by @normanmaurer in #16882

Full Changelog: netty-4.1.134.Final...netty-4.1.135.Final

What's Changed

• HTTP: Fix revapi failure introduced by 84530fa by @normanmaurer in #16748
• HTTP: Re-add constructor to HttpProxyHandler that was removed by mistake by @normanmaurer in #16747
• Marshalling: Explicit document security requirements by @normanmaurer in #16752
• Fix io_uring op completion TRACE logging by @chrisvest in #16755
• Quic: Ensure writes are done before notify close promise of QuicheQui… by @normanmaurer in #16758
• Avoid re-parsing openssl key material with non-cached provider by @chrisvest in #16759
• Pin HTTP/RTSP version + method normalization to Locale.US by @daguimu in #16765
• Fill MsgHdrMemoryArray#hdrs with null entry on release by @tsegismont in #16764
• Revapi: Use default "oldVersion" by @chrisvest in #16774
• Adaptive: Fix concurrency issue in adaptive allocator by @chrisvest in #16767
• Auto-port 4.2: Make bulk byte moving in ByteBuf faster by @netty-project-bot in #16781
• Pin multipart Content-Type / Content-Transfer-Encoding case folding to Locale.US by @daguimu in #16768
• Remove dead native declarations by @pandareen in #16783
• Isolate tests that modify available Security providers by @chrisvest in #16793
• Remove test annotations from a method that isn't a test by @chrisvest in #16792
• Enable OpenSslCachingKeyMaterialProvider to evict stale entries after cert rotation by @zhangweikop in #16523
• IoUring: extend user data from short to long by @dreamlike-ocean in #16682
• Revert CompositeByteBuf component search fast path by @yawkat in #16811
• HTTP2: Use 100 as default max concurrent streams setting by @normanmaurer in #16804
• Fix ResumptionController wrapping by @chrisvest in #16815
• Resolve all localhost addresses without querying DNS servers by @JulianVennen in #16749
• IpFilter: Fix ClassCastException caused by IpSubnetFilter if only ipv6 rules are configured but remote peer is using ipv4 by @normanmaurer in #16803
• Fix memoryAddress() for direct ByteBuffers wrapped by Unpooled without Unsafe by @dreamlike-ocean in #16788
• Route synchronous onLookupComplete exceptions via fireExceptionCaught by @kwondh5217 in #16794
• IoUring: Stop generic FileRegion drain loop when transferred() reaches count() by @LuciferYang in #16826
• MQTT: Allow MQTT 5 CONNECT with password only by @shblue21 in #16833
• Fix MQTT decoder size check after variable header replay by @daguimu in #16787

New Contributors

• @pandareen made their first contribution in #16783
• @zhangweikop made their first contribution in #16523
• @JulianVennen made their first contribution in #16749
• @kwondh5217 made their first contribution in #16794
• @shblue21 made their first contribution in #16833

Full Changelog: netty-4.2.13.Final...netty-4.2.14.Final

What's Changed

• Auto-port 4.1: HTTP: Re-add constructor to HttpProxyHandler that was removed by mistake by @netty-project-bot in #16750
• Auto-port 4.1: Marshalling: Explicit document security requirements by @netty-project-bot in #16754
• Pin HTTP/RTSP version + method normalization to Locale.US (#16765) by @normanmaurer in #16770
• Adaptive: Fix concurrency issue in adaptive allocator (#16767) by @chrisvest in #16778
• Pin multipart Content-Type / Content-Transfer-Encoding case folding t… by @normanmaurer in #16784
• Auto-port 4.1: Remove dead native declarations by @netty-project-bot in #16785
• Avoid re-parsing openssl key material with non-cached provider (#16759) by @chrisvest in #16791
• Isolate tests that modify available Security providers (#16793) by @chrisvest in #16805
• Auto-port 4.1: Remove test annotations from a method that isn't a test by @netty-project-bot in #16798
• Auto-port 4.1: IpFilter: Fix ClassCastException caused by IpSubnetFilter if only ipv6 rules are configured but remote peer is using ipv4 by @netty-project-bot in #16822
• Resolve all localhost addresses without querying DNS servers (#16749) by @normanmaurer in #16820
• Auto-port 4.1: HTTP2: Use 100 as default max concurrent streams setting by @netty-project-bot in #16816
• Auto-port 4.1: Route synchronous onLookupComplete exceptions via fireExceptionCaught by @netty-project-bot in #16824
• Auto-port 4.1: Fix MQTT decoder size check after variable header replay by @netty-project-bot in #16838

Full Changelog: netty-4.1.133.Final...netty-4.1.134.Final

CVEs Fixed

• CVE-2026-42586 (netty-codec-redis)
• CVE-2026-42578 (netty-handler-proxy)
• CVE-2026-42577 (netty-transport-native-epoll)
• CVE-2026-42587 (netty-codec-http, netty-codec-http2)
• CVE-2026-41417 (netty-codec-http)
• CVE-2026-42581 (netty-codec-http)
• CVE-2026-42580 (netty-codec-http)
• CVE-2026-42585 (netty-codec-http)
• CVE-2026-42579 (netty-codec-dns)
• CVE-2026-42582 (netty-codec-http3)
• CVE-2026-42583 (netty-codec, netty-codec-compression)
• CVE-2026-42584 (netty-codec-http)
• CVE-2026-44248 (netty-codec-mqtt)

Breaking Changes

The patch for CVE-2026-42581 prohibits HTTP/1.1 requests containing both the Transfer-Encoding and Content-Length headers, in line with RFC 9112. Previous versions of HTTP/1.1 (RFC 7230) permitted this combination. You can restore the old behavior with the -Dio.netty.handler.codec.http.rfc9112TransferEncoding=false system property or with HttpDecoderConfig. Note that disabling this check may lead to request smuggling vulnerabilities.

What's Changed

• Kqueue: sendfile EINTR doesn't advance offset — data duplication by @normanmaurer in #16544
• Replace usage of strerror with thread-safe alternative by @normanmaurer in #16547
• Fix implementation of strerror_r_xsi for GNU by @normanmaurer in #16546
• Lazy init ArrayList in DefaultHeaders.getAll by @doom369 in #16526
• Less logging in AWS-LC build by @chrisvest in #16565
• Ensure the CRYPTO_BUFFER_POOL is also freed when we fail creating the SSLContext by @normanmaurer in #16545
• Auto-port 4.2: Fix IndexOutOfBoundsException in StompSubframeDecoder on heartbeat by @netty-project-bot in #16543
• Avoid leak in PemReader on OutOfDirectMemoryError by @raipc in #16551
• IoUring: Disable test while we debug to unblock other builds by @normanmaurer in #16581
• Include user properties and subscription IDs in MqttProperties#isEmpty by @ShadowySpirits in #16575
• Native DNS resolver: Guard against malloc failures by @normanmaurer in #16559
• Auto-port 4.2: Increase timeouts for QuicChannelConnectTest by @netty-project-bot in #16578
• Fix parsing HTTP chunks with multiple extensions by @chrisvest in #16579
• Bump org.codehaus.plexus:plexus-utils from 3.4.2 to 4.0.3 in /codec-native-quic by @dependabot[bot] in #16572
• Revert to PR build to Ubuntu 22.04 by @chrisvest in #16595
• Native transports: Correctly create pipe when pipe2 is not supported by @normanmaurer in #16592
• Epoll: Cleanup code to always return negative value on failure by @normanmaurer in #16591
• Fix component search fast path by @yawkat in #16548
• Stabilize read-only toStringMultipleThreads1 by @chrisvest in #16608
• Stabilize more AbstractByteBufTests by @chrisvest in #16611
• Remove note about needing 256-bit for PQC by @chrisvest in #16605
• Stabilize testSessionInvalidate for Conscrypt by @chrisvest in #16615
• Quic: Correctly handle SSL_CTX_new failures by @normanmaurer in #16622
• Make LocalIoHandle public by @rdicroce in #16621
• Quic: Fix shadowing of variable which leads to incorrectly handling errors by @normanmaurer in #16623
• Auto-port 4.2: Use stream error for maxContentLength exceeded in InboundHttp2ToHttpAdapter by @netty-project-bot in #16629
• Fix shutdownInput bug in kqueue for empty recv buffer by @chrisvest in #16630
• fix FFM address semantics in directBufferAddress by @dreamlike-ocean in #16603
• HTTP2: Ensure HTTP2 preface is always send as first message by @normanmaurer in #16636
• Move Http2FrameCodecSubClassTest to correct package by @normanmaurer in #16640
• Kqueue: Fix usage of LOCAL_PEERPID by @normanmaurer in #16637
• Avoid ArrayQueue allocation in HttpServerCodec by @doom369 in #16596
• Fix file descriptor reuse bug in kqueue by @chrisvest in #16650
• Propagate exceptions from inner threads in buffer tests by @chrisvest in #16643
• Add maxFrameLength support to ProtobufVarint32FrameDecoder by @fru1tworld in #16633
• Avoid byte[] allocation in DefaultChannelId by @doom369 in #16631
• Bump BouncyCastle from 1.83 to 1.84 by @chrisvest in #16660
• HTTP2: Ensure HTTP2 preface is always send as first message (also on the server) by @normanmaurer in #16667
• Update outdated codec-http3 README.md by @fru1tworld in #16665
• Bump up netty-tcnative to 2.0.76.Final by @normanmaurer in #16669
• Fix IllegalReferenceCountException in AdaptiveByteBuf.deallocate() by @gzsombor in #16654
• Skip VarHandle init when unaligned access is supported by @Songdoeon in #16664
• Add generic FileRegion support in io_uring stream channel by @LuciferYang in #16571
• ByteBufAllocatorAllocPatternBenchmark: Ensure each index appears exactly once in releaseIndexes by @laosijikaichele in #16604
• Improve flaky NioSocketChannelTest by @chrisvest in #16679
• Deprecate ObjectCleaner and remove usage by @chrisvest in #16685
• Update to netty-tcnative 2.0.77.Final by @normanmaurer in #16687
• Avoid TCPFastOpen in KQueueCompositeBufferGatheringWriteTest by @chrisvest in #16697
• Update JUnit to 5.14.0 and fix leak scope handling by @yawkat in #16680
• Auto-port 4.2: Avoid NPE in JdkSslClientContext when TrustManagerFactory returns null by @netty-project-bot in #16702
• Avoid NPE in JdkSslServerContext when TrustManagerFactory returns nul… by @normanmaurer in #16700
• IoUring: Fix incorrect assertion which was triggered when two Channel… by @normanmaurer in #16705
• Epoll: Correctly delete fd from epoll if there is nothing to handle by @normanmaurer in #16689
• Update many dependencies by @chrisvest in #16707
• SCTP: Correctly handle SO_BACKLOG by @normanmaurer in #16714
• Load BouncyCastle providers independently by @chrisvest in #16710
• Add UBI9 devcontainer by @chrisvest in #16711
• Consolidate fake exceptions in HTTP/2 tests into Http2TestUtil by @fru1tworld in #16712
• Auto-port 4.2: Fix DiscardClient hang under -Dssl by using a client SSL context by @netty-project-bot in #16724
• Epoll: Use correct inital EpollIoOps by @normanmaurer in #16728
• Activate noPrintGC by default by @chrisvest in #16732
• H2: Add test for header value validation by @chrisvest in #16737

New Contributors

• @ShadowySpirits made their first contribution in #16575
• @fru1tworld made their first contribution in #16633
• @gzsombor made their first contribution in #16654
• @LuciferYang made their first contribution in #16571

Full Changelog: netty-4.2.12.Final...netty-4.2.13.Final

CVEs Fixed

• CVE-2026-42586 (netty-codec-redis)
• CVE-2026-42578 (netty-handler-proxy)
• CVE-2026-42587 (netty-codec-http, netty-codec-http2)
• CVE-2026-41417 (netty-codec-http)
• CVE-2026-42581 (netty-codec-http)
• CVE-2026-42580 (netty-codec-http)
• CVE-2026-42585 (netty-codec-http)
• CVE-2026-42579 (netty-codec-dns)
• CVE-2026-42582 (netty-codec-http3)
• CVE-2026-42583 (netty-codec, netty-codec-compression)
• CVE-2026-42584 (netty-codec-http)
• CVE-2026-44248 (netty-codec-mqtt)

What's Changed

• Fix IndexOutOfBoundsException in StompSubframeDecoder on heartbeat by @daguimu in #16539
• Auto-port 4.1: Fix implementation of strerror_r_xsi for GNU by @netty-project-bot in #16561
• Auto-port 4.1: Replace usage of strerror with thread-safe alternative by @netty-project-bot in #16555
• Auto-port 4.1: Kqueue: sendfile EINTR doesn't advance offset — data duplication by @netty-project-bot in #16554
• Auto-port 4.1: Avoid leak in PemReader on OutOfDirectMemoryError by @netty-project-bot in #16576
• Auto-port 4.1: Native DNS resolver: Guard against malloc failures by @netty-project-bot in #16584
• Auto-port 4.1: Include user properties and subscription IDs in MqttProperties#isEmpty by @netty-project-bot in #16582
• Auto-port 4.1: Fix parsing HTTP chunks with multiple extensions by @netty-project-bot in #16588
• Auto-port 4.1: Stabilize read-only toStringMultipleThreads1 by @netty-project-bot in #16610
• Auto-port 4.1: Epoll: Cleanup code to always return negative value on failure by @netty-project-bot in #16601
• Auto-port 4.1: Stabilize more AbstractByteBufTests by @netty-project-bot in #16613
• Auto-port 4.1: Stabilize testSessionInvalidate for Conscrypt by @netty-project-bot in #16616
• Auto-port 4.1: Native transports: Correctly create pipe when pipe2 is not supported by @netty-project-bot in #16598
• Use stream error for maxContentLength exceeded in InboundHttp2ToHttpAdapter by @daguimu in #16558
• Fix shutdownInput bug in kqueue for empty recv buffer (#16630) by @normanmaurer in #16638
• Auto-port 4.1: Kqueue: Fix usage of LOCAL_PEERPID by @netty-project-bot in #16646
• Auto-port 4.1: HTTP2: Ensure HTTP2 preface is always send as first message by @netty-project-bot in #16642
• Auto-port 4.1: Propagate exceptions from inner threads in buffer tests by @netty-project-bot in #16652
• Auto-port 4.1: Add maxFrameLength support to ProtobufVarint32FrameDecoder by @netty-project-bot in #16658
• Auto-port 4.1: Bump up netty-tcnative to 2.0.76.Final by @netty-project-bot in #16672
• HTTP2: Ensure HTTP2 preface is always send as first message (also on … by @chrisvest in #16675
• Improve flaky NioSocketChannelTest (#16679) by @normanmaurer in #16681
• Deprecate ObjectCleaner and remove usage (#16685) by @chrisvest in #16694
• Auto-port 4.1: Update to netty-tcnative 2.0.77.Final by @netty-project-bot in #16695
• Avoid NPE in JdkSslServerContext when TrustManagerFactory returns null by @daguimu in #16691
• Avoid NPE in JdkSslClientContext when TrustManagerFactory returns null by @daguimu in #16690
• Auto-port 4.1: Avoid TCPFastOpen in KQueueCompositeBufferGatheringWriteTest by @netty-project-bot in #16699
• Auto-port 4.1: SCTP: Correctly handle SO_BACKLOG by @netty-project-bot in #16715
• Fix DiscardClient hang under -Dssl by using a client SSL context by @daguimu in #16717
• Auto-port 4.1: Consolidate fake exceptions in HTTP/2 tests into Http2TestUtil by @netty-project-bot in #16725
• Auto-port 4.1: Activate noPrintGC by default by @netty-project-bot in #16735
• Merge commit from fork by @normanmaurer in #16742

New Contributors

• @daguimu made their first contribution in #16539

Full Changelog: netty-4.1.132.Final...netty-4.1.133.Final

What's Changed

• Revert "Eliminate redundant bounds checks in CompositeByteBuf accessors" by @chrisvest in #16550

Full Changelog: netty-4.2.11.Final...netty-4.2.12.Final

Security

• CVE-2026-33871, HTTP/2 CONTINUATION Frame Flood Denial of Service
• CVE-2026-33870, HTTP Request Smuggling via Chunked Extension Quoted-String Parsing

What's Changed

• Update to latest JDK 26 EA release by @normanmaurer in #16230
• HTTP3: Allow to support non-standard HTTP3 settings by @normanmaurer in #16171
• Fix Incorrect nanos-to-millis conversion in epoll_wait EINTR retry loop by @adwsingh in #16245
• Allocate one large segment and slice for each MsgHdrMemory by @dreamlike-ocean in #16234
• Make RefCntOpenSslContext.deallocate more robust by @chrisvest in #16253
• Epoll: Fix excessive CPU usage when Channel is only registered but no… by @normanmaurer in #16250
• Update to gcc for arm 10.3-2021.07 by @m1ngyuan in #16255
• Add acmeIdentifier extension support to pkitesting by @chrisvest in #16256
• Update JDK versions to latest patch releases by @m1ngyuan in #16254
• Avoid allocation in HttpObjectEncoder.addEncodedLengthHex method by @doom369 in #16241
• Automatic backporting workflow from 4.1 to 4.2 by @chrisvest in #16269
• Revert "Automatic backporting workflow from 4.1 to 4.2" by @chrisvest in #16270
• HTTP2: Correctly account for padding when decompress by @normanmaurer in #16264
• Automatic backporting workflow from 4.1 to 4.2 by @chrisvest in #16271
• Automatic backporting workflow from 4.1 to 4.2 by @chrisvest in #16273
• Backport PRs must be created with personal access tokens by @chrisvest in #16276
• Expose QuicSslContextBuilder::sni by @ZeroErrors in #16178
• Add more porting workflows by @chrisvest in #16275
• Add more porting workflows by @chrisvest in #16283
• Remove the unpooled allocator from test permutations by @chrisvest in #16282
• Some polishing of the porting workflows by @chrisvest in #16288
• Allow to set destination connection id when creating a client side QuicheChannel by @normanmaurer in #16286
• Update to latest JDK26 EA build by @normanmaurer in #16295
• Add javadoc to clarify responsibility of the user when generating the remote connection id by @normanmaurer in #16293
• Make the build run faster by @chrisvest in #16290
• Fix IDE warnings in SslHandler by @doom369 in #16237
• Decrease Long allocations and map.put calls in ReferenceCountedOpenSllEngine in handshake() method by @doom369 in #16242
• Support boringssl SSLCredential API by @jmcrawford45 in #15919
• Fix high-order bit aliasing in HttpUtil.validateToken by @furkanvarol in #16279
• Improve multi-byte access performance when UNALIGNED availability is unknown by @Songdoeon in #16207
• Avoid unnecessary SSL.getVersion() call and string allocation in ReferenceCountedOpenSslEngine by @doom369 in #16278
• Support more branch freedom for auto-porting by @chrisvest in #16300
• fix: the precedence of + is higher than >> by @cuiweixie in #16312
• AdaptiveByteBufAllocator: make sure byteBuf.capacity() not greater than byteBuf.maxCapacity() by @laosijikaichele in #16309
• Fix flaky PooledByteBufAllocatorTest by @chrisvest in #16313
• Fix pooled arena accounting tests by @chrisvest in #16321
• Fix RunInFastThreadLocalThreadExtension by @chrisvest in #16314
• AdaptivePoolingAllocator: call unreserveMatchingBuddy(...) if byteBuf initialization failed by @laosijikaichele in #16327
• Recycler should not use thread locals unless they get cleaned up by @chrisvest in #16315
• OpenSSL: Don't leak OpenSslKeyManagerProvider on exception by @normanmaurer in #16337
• IoUring: Only complete deregistration promise once we received all co… by @normanmaurer in #16330
• Mark LoggingHandlerTest with @isolated to fix flaky build by @normanmaurer in #16338
• Fix flaky HTTP/2 test by @chrisvest in #16342
• Fix HTTP/2 push frame test by @chrisvest in #16343
• Fix flaky RenegotiateTest by @chrisvest in #16351
• IoUring: Don't use RDHUP for non stream Channel implementations by @normanmaurer in #16345
• SSL test: Don't depend on property value in test by @normanmaurer in #16346
• Fix flaky AbstractSingleThreadEventLoopTest by @chrisvest in #16352
• Use headers.setInt() in HttpObjectAggregator instead of set() and use concrete version of String.valueOf in CharSequenceValueConverter by @doom369 in #16239
• IoUring: Fix buffer leak in DatagramChannel implementation when recv … by @normanmaurer in #16359
• Don't assume CertificateFactory is thread-safe by @chrisvest in #16350
• AdaptivePoolingAllocator: assign a more explicit value to BuddyChunk.freeListCapacity by @laosijikaichele in #16334
• Fix leak in SniHandlerTest by @chrisvest in #16367
• Add more diagnostic points to PooledByteBufAllocatorTest.createNewThr… by @chrisvest in #16365
• Stabilize AbstractByteBufTest.testBytesInArrayMultipleThreads by @chrisvest in #16370
• Avoid unnecessary Long.toString() allocation in HttpObjectDecoder by @doom369 in #16344
• Remove reference counting from size classed chunks by @franz1981 in #16306
• Stabilize AbstractByteBufTest.testToStringMultipleThreads by @chrisvest in #16380
• Swap conditions to avoid native calls in ReferenceCountedOpenSslEngine.rejectRemoteInitiatedRenegotiation by @doom369 in #16389
• Remove duplicated contains calls in WebSockets by @doom369 in #16388
• IoUring: Reduce unnecessary io_uring_enter syscalls on non-blocking path by @dreamlike-ocean in #16259
• Fix NioIoHandlerTest on macOS by @chrisvest in #16396
• LocalChannel: Remove dependency on SingleThreadEventExecutor by @normanmaurer in #16393
• Fix autoport fetching into the existing branch by @chrisvest in #16403
• HTTP2: Pass the correct number of arguments when logging goaway by @normanmaurer in #16392
• Revert "Fix autoport fetching into the existing branch" by @chrisvest in #16410
• Fix HttpObjectAggregator leaving connection stuck after 413 with AUTO (#16280) by @chrisvest in #16401
• Fix autoport fetching into the existing branch - again by @chrisvest in #16411
• Fix typo in AbstractEpollChannel: 'inital' → 'initial' by @nikitanagar08 in #16415
• Capture why threads get stuck in testCopyMultipleThreads0 by @chrisvest in #16404
• Local transport: shutdown hook should call closeNow to be conistent with what LocalIoHandler will call by @normanmaurer in #16406
• Remove unnecessary array access in DefaultAttributeMap.orderedCopyOnInsert by @doom369 in #16386
• Whitelist JMH annotation processing in microbench module by @laosijikaichele in #16428
• Fire the QuicChannel datagram extension event before the channel becomes active by @vietj in #16425
• HTTP2: Ensure preface is flushed in all cases by @normanmaurer in #16407
• Support QuicheQuicSslEngine hostname identification algorithm. by @vietj in #16426
• Fix client_max_window_bits parameter handling in permessage-deflate extension by @nikitanagar08 in #16424
• Fix UnsupportedOperationException in readTrailingHeaders by @furkanvarol in #16412
• IoUring: Fix io_uring writev infinite loop on kernels without SENDMSG_ZC support by @dreamlike-ocean in #16438
• Kqueue: Correctly handle registrations by @normanmaurer in #16439
• Kqueue: C...