CVE-2026-42583: high-severity vulnerability in netty
Netty: Lz4FrameDecoder resource exhaustion
Published · Updated
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21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.5epss 0.5%
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
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