high7.5
CVE-2026-42583
Netty is an asynchronous, event-driven network application framework.
Impact
Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, Lz4FrameDecoder allocates a ByteBuf of size decompressedLength (up to 32 MB per block) before LZ4 runs. A peer only needs a 21-byte header plus compressedLength payload bytes - 22 bytes if compressedLength == 1 - to force that allocation. This vulnerability is fixed in 4.2.13.Final and 4.1.133.Final.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| maven | io.netty:netty-codec-compression | <= 4.2.12.Final | 4.2.13.Final |
| maven | io.netty:netty-codec | <= 4.1.132.Final | 4.1.133.Final |
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Netty | Netty | before 4.1.133 from 4.2.0 before 4.2.13 |