Description
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 products
netty: netty
References2
- github.com/netty/netty/security/advisories/GHSA-mj4r-2hfc-f8p6 ExploitVendor Advisory
- github.com/netty/netty/security/advisories/GHSA-mj4r-2hfc-f8p6 ExploitVendor Advisory
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 41 · as of 14 November 2026
- CWE
- CWE-400CWE-770
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