CVE-2026-54251: Netty netty-incubator-codec-ohttp memory leak in AEAD decryption

CVE-2026-54251 · Severity: high · CVSS 4 · Published 2026-09-15

The netty-incubator-codec-ohttp library is used by OHTTP gateways to process encrypted client requests. When the gateway receives a tampered or invalid encrypted message, it fails to release a block of allocated native memory, allowing attackers to send crafted requests that exhaust available memory and crash the gateway service, disrupting availability for legitimate users.

Technologies: io.netty.incubator:netty-incubator-codec-ohttp (Maven), Netty Project Netty Incubator Codec OHTTP. Vendors: Maven, Netty Project.

Quick answers

Is CVE-2026-54251 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-54251 being exploited in the wild.
How severe is CVE-2026-54251?
High severity, with a CVSS score of 4, published 15 September 2026.
Which products and versions are affected?
io.netty.incubator:netty-incubator-codec-ohttp (Maven) < 0.0.23.Final, ECOSYSTEM:introduced=0,fixed=0.0.23.Final; Netty Project Netty Incubator Codec OHTTP < 0.0.23.Final.
Is there a fix for CVE-2026-54251?
Yes. io.netty.incubator:netty-incubator-codec-ohttp (Maven): upgrade to 0.0.23.Final or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-54251 attacked?
It is attacked over the network, in a software library.
Am I affected by CVE-2026-54251?
Check whether you run io.netty.incubator:netty-incubator-codec-ohttp (Maven) or Netty Project Netty Incubator Codec OHTTP at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • io.netty.incubator:netty-incubator-codec-ohttp (Maven): upgrade to 0.0.23.Final or later
    # set io.netty.incubator:netty-incubator-codec-ohttp to 0.0.23.Final in your pom.xml or build.gradle

Technical details

The vulnerability is a resource leak (CWE-664) in the OHttpServerCodec class during AEAD (Authenticated Encryption with Associated Data) decryption. When processing an encrypted OHTTP client request, the codec allocates a pooled direct ByteBuf to hold the decrypted plaintext before verifying the AEAD authentication tag. If the authentication tag check fails (indicating invalid or tampered ciphertext), the decryption method throws a CryptoException, but the allocated buffer is never released due to missing try/finally block guards. An attacker can trigger this leak repeatedly by sending malformed encrypted requests to a gateway over the network without authentication, causing native memory exhaustion and denial of service. The vulnerability is fixed in version 0.0.23.Final.

Affected products

  • Netty netty-incubator-codec-ohttp < 0.0.23.Final

Identifiers

  • CVE-2026-54251
  • GHSA-vmr9-j6wf-pmh2

Timeline

  • 2026-07-09: disclosed: Advisory published
  • 2026-07-10: patched: Fix released in version 0.0.23.Final

References

This page as Markdown. Free to reuse under CC BY 4.0 with a link back.