Netty: SNI handler pre-allocates up to 16 MiB from nine attacker bytes

SslClientHelloHandler.decode reads the 24-bit TLS handshake length and, when the ClientHello does not fit in the first record, eagerly allocates ctx.alloc.bufferhandshakeLength line 161. The guard at line 140 is handshakeLength maxClientHelloLength && maxClientHelloLength != 0, and the...

GHSA-X4GW-5CX5-PGMH Netty: SNI handler pre-allocates up to 16 MiB from nine attacker bytes

SslClientHelloHandler.decode reads the 24-bit TLS handshake length and, when the ClientHello does not fit in the first record, eagerly allocates ctx.alloc.bufferhandshakeLength line 161. The guard at line 140 is handshakeLength maxClientHelloLength && maxClientHelloLength != 0, and the...

Netty's Default QUIC token handler accepts any client-supplied token

NoQuicTokenHandler is the tokenHandler used when the application does not set one. Its writeToken returns false server will not send Retry — acceptable, but validateToken unconditionally return 0. In QuicheQuicServerCodec.handlePacket, a non-negative return from validateToken is interpreted as...

Improper Verification of Source of a Communication Channel

Overview Affected versions of this package are vulnerable to Improper Verification of Source of a Communication Channel due to improper validation in the validateToken function. An attacker can cause the server to treat unvalidated client addresses as validated by supplying any non-empty token...

GHSA-CMM3-54F8-PX4J Netty's Default QUIC token handler accepts any client-supplied token

NoQuicTokenHandler is the tokenHandler used when the application does not set one. Its writeToken returns false server will not send Retry — acceptable, but validateToken unconditionally return 0. In QuicheQuicServerCodec.handlePacket, a non-negative return from validateToken is interpreted as...

Missing Release of Resource after Effective Lifetime

Overview Affected versions of this package are vulnerable to Missing Release of Resource after Effective Lifetime through improper handling of TLV length in the readNextTLV function. An attacker can cause resource exhaustion and denial of service by sending a specially crafted HAProxy protocol...

Netty: HAProxy SSL TLV parsing leaks retained slice on invalid TLV length

When decoding a PP2TYPESSL TLV, HAProxyMessage.readNextTLV first calls header.retainedSliceheader.readerIndex, length and only then reads the 1-byte client field and 4-byte verify field. If the attacker sets the TLV length below 5, the subsequent readByte/readInt throws IndexOutOfBoundsException...

GHSA-CC37-9Q2J-3HFV Netty: HAProxy SSL TLV parsing leaks retained slice on invalid TLV length

When decoding a PP2TYPESSL TLV, HAProxyMessage.readNextTLV first calls header.retainedSliceheader.readerIndex, length and only then reads the 1-byte client field and 4-byte verify field. If the attacker sets the TLV length below 5, the subsequent readByte/readInt throws IndexOutOfBoundsException...

GHSA-C2RX-5R8W-8XR2 Netty has a Vulnerable Default Configuration Which Leads to Denial of Service via Unbounded HTTP/3 Header Size

Summary The default configuration of the Http3ConnectionHandler in the Netty HTTP/3 codec lacks an enforced maximum header size limit. When a peer does not explicitly specify HTTP3SETTINGSMAXFIELDSECTIONSIZE, the implementation defaults to an unbounded limit. This insecure default configuration...

Netty has a Vulnerable Default Configuration Which Leads to Denial of Service via Unbounded HTTP/3 Header Size

Summary The default configuration of the Http3ConnectionHandler in the Netty HTTP/3 codec lacks an enforced maximum header size limit. When a peer does not explicitly specify HTTP3SETTINGSMAXFIELDSECTIONSIZE, the implementation defaults to an unbounded limit. This insecure default configuration...

Insecure Default Initialization of Resource

Overview Affected versions of this package are vulnerable to Insecure Default Initialization of Resource due to the lack of an enforced maximum header size limit in the default configuration of the Http3ConnectionHandler. An attacker can exhaust server memory and cause application crashes by...

Allocation of Resources Without Limits or Throttling

Overview Affected versions of this package are vulnerable to Allocation of Resources Without Limits or Throttling through the decodeLength function. An attacker can exhaust the server's direct memory pool by sending continuous streams of digits without a terminating \r\n across multiple concurren...

Netty has Unbounded Direct Memory Consumption in its RedisDecoder

Summary An attacker can cause DoS by sending crafted Redis payloads across multiple connections without \r\n. This exhausts the server's direct memory pool OutOfDirectMemoryError, preventing legitimate connections from being processed. Details io.netty.handler.codec.redis.RedisDecoder decodes the...

GHSA-6GHJ-FRRJ-JJJ3 Netty has Unbounded Direct Memory Consumption in its RedisDecoder

Summary An attacker can cause DoS by sending crafted Redis payloads across multiple connections without \r\n. This exhausts the server's direct memory pool OutOfDirectMemoryError, preventing legitimate connections from being processed. Details io.netty.handler.codec.redis.RedisDecoder decodes the...

GHSA-3244-J874-RHC2 Netty: Memory Exhaustion in RedisArrayAggregator due to Deeply Nested Arrays

Summary An attacker can cause DoS by sending a crafted Redis payload with deeply nested arrays. This forces the server to allocate a massive number of state objects and collections, leading to memory exhaustion and an OutOfMemoryError. Details io.netty.handler.codec.redis.RedisArrayAggregator...

Netty: Memory Exhaustion in RedisArrayAggregator due to Deeply Nested Arrays

Summary An attacker can cause DoS by sending a crafted Redis payload with deeply nested arrays. This forces the server to allocate a massive number of state objects and collections, leading to memory exhaustion and an OutOfMemoryError. Details io.netty.handler.codec.redis.RedisArrayAggregator...

Denial of Service (DoS)

Overview Affected versions of this package are vulnerable to Denial of Service DoS in the RedisArrayAggregator function. An attacker can exhaust system memory by sending specially crafted Redis payloads containing deeply nested arrays, resulting in allocation of excessive state objects and...

Incorrect Comparison

Overview io.netty:netty-handler is a library that provides an asynchronous event-driven network application framework and tools for rapid development of maintainable high performance and high scalability protocol servers and clients. In other words, Netty is a NIO client server framework which...

Netty has an IPv6 Subnet Filter Bypass via Incorrect Comparator Masking

Summary An attacker can bypass IPv6 subnet rules due to an incorrect masking operation in IpSubnetFilterRule.compareTo. Valid public IP addresses can bypass the restrictions. Details io.netty.handler.ipfilter.IpSubnetFilterRulecompareTojava.net.InetSocketAddress method performs a bitwise AND...

Security Bulletin: IBM Datapower Operations Dashboard is vulnerable to HTTP Request Smuggling CVE-2025-58056

Summary Netty is used by the IBM Datapower Operations Dashboard as part of their server implementation Vulnerability Details CVEID:CVE-2025-58056 DESCRIPTION: Netty is an asynchronous event-driven network application framework for development of maintainable high performance protocol servers and...