Netty published
a security advisory of a crash in SslHandler. grpc-java's usage of Netty uses newEngine() for both
client and
server, so is not vulnerable. This means grpc-netty and grpc-netty-shaded are not vulnerable. I looked at recent and ancient history and believe no grpc-java version to be vulnerable (e.g., an
old commit from 2015 was using newEngine()).
Good dependency hygiene would still dictate upgrading io.netty if it is in your dependency tree.