NetSight
IP …
medium5.3

CVE-2026-48043

netty-codec-http2: ByteBuf Reference-Count Leak in DelegatingDecompressorFrameListener Leads to Memory Exhaustion

Impact

Netty is a network application framework for development of protocol servers and clients. In netty-codec-http2 prior to versions 4.1.135.Final and 4.2.15.Final, the `DelegatingDecompressorFrameListener` class orchestrates HTTP/2 decompression by embedding a per-stream `EmbeddedChannel` that runs the appropriate decompression codec (gzip, deflate, zstd) and forwards decompressed chunks to a wrapped listener. Each decompressed chunk is a pooled `ByteBuf` handed to an anonymous `ChannelInboundHandlerAdapter` tail handler, which becomes the sole owner responsible for releasing it. A remote peer could send frames that would result in the flow-controller throwing and so trigger a resource leak which at the end might take down the whole JVM due OOME. Versions 4.1.135.Final and 4.2.15.Final patch the issue.

Affected packages

EcosystemPackageAffectedFixed in
mavenio.netty:netty-codec-http2<= 4.1.134.Final4.1.135.Final

Affected products

VendorProductAffected versions
NettyNetty
before 4.1.135
from 4.2.0 before 4.2.15

Weakness classification

CWE-400CWE-401CWE-772

References