NetSight
IP …
high7.5

CVE-2026-46340

Netty is a network application framework for development of protocol servers and clients.

Impact

Netty is a network application framework for development of protocol servers and clients. In versions of netty-transport-sctp prior to 4.1.135.Final and 4.2.15.Final, for each non-complete SctpMessage fragment the handler does `fragments.put(streamId, Unpooled.wrappedBuffer(frag, byteBuf))`, wrapping the previous accumulator and the new slice into a *new* CompositeByteBuf every time. After N fragments the accumulator is an N-deep chain of composites, each holding references and component arrays; readableBytes()/getBytes() on the final buffer recurse N levels. There is no limit on N, on total bytes, or on the number of streamIdentifiers an attacker can open (each gets its own map entry). A peer that never sets the `complete` flag can grow this structure indefinitely from tiny 1-byte DATA chunks. Versions 4.1.135.Final and 4.2.15.Final patch the issue.

Affected packages

EcosystemPackageAffectedFixed in
mavenio.netty:netty-transport-sctp>= 4.2.0.Final, <= 4.2.14.Final4.2.15.Final

Affected products

VendorProductAffected versions
NettyNetty
before 4.1.135
from 4.2.0 before 4.2.15

Weakness classification

CWE-770

References