Detections
Analytics
CVE-2026-42587
high
Description
Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, HttpContentDecompressor accepts a maxAllocation parameter to limit decompression buffer size and prevent decompression bomb attacks. This limit is correctly enforced for gzip and deflate encodings via ZlibDecoder, but is silently ignored when the content encoding is br (Brotli), zstd, or snappy. An attacker can bypass the configured decompression limit by sending a compressed payload with Content-Encoding: br instead of Content-Encoding: gzip, causing unbounded memory allocation and out-of-memory denial of service. The same vulnerability exists in DelegatingDecompressorFrameListener for HTTP/2 connections. This vulnerability is fixed in 4.2.13.Final and 4.1.133.Final.
References
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-42587.json
https://github.com/netty/netty/security/advisories/GHSA-f6hv-jmp6-3vwv
https://bugzilla.redhat.com/show_bug.cgi?id=2477220
https://access.redhat.com/security/cve/CVE-2026-42587
https://access.redhat.com/errata/RHSA-2026:37390
https://access.redhat.com/errata/RHSA-2026:36820
https://access.redhat.com/errata/RHSA-2026:34608
https://access.redhat.com/errata/RHSA-2026:28010
https://access.redhat.com/errata/RHSA-2026:25123