Description
Netty is an asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers & clients. In netty-codec-compression versions 4.1.124.Final and below, and netty-codec versions 4.2.4.Final and below, when supplied with specially crafted input, BrotliDecoder and certain other decompression decoders will allocate a large number of reachable byte buffers, which can lead to denial of service. 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 fixed in versions 4.1.125.Final of netty-codec and 4.2.5.Final of netty-codec-compression.
Affected products
netty: netty
References2
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - CVSS 4.0
-
6.9
MEDIUM
Score source: CNA
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 1% percentile: 51 · as of 8 November 2026
- CWE
- CWE-409
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