CVE-2026-54251: netty-incubator-codec-ohttp: [OHttpServerCodec] Native Direct-Memory Leak on AEAD Decryption Failure Leads to Gateway Denial of Service

The netty-incubator-codec-ohttp library implements Oblivious HTTP (OHTTP) gateway and client functionality using Netty’s ByteBuf memory management. When an OHTTP gateway processes encrypted client requests, it allocates a pooled direct (native off-heap) ByteBuf to hold the decrypted plaintext before the AEAD tag is verified. If the AEAD tag check fails — meaning the ciphertext is invalid — the decryption method throws a CryptoException, but the allocated buffer is never released because no try/finally block guards the allocation.