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

Source: https://junglewise.ai/threats/cve-2026-54251-netty-netty-incubator-codec-ohttp-memory-leak-in-aead-decryption  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-15. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

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)](https://junglewise.ai/threats/technologies/io-netty-incubator-netty-incubator-codec-ohttp), [Netty Project Netty Incubator Codec OHTTP](https://junglewise.ai/threats/technologies/incubator-codec-ohttp). Vendors: [Maven](https://junglewise.ai/threats/vendors/maven), [Netty Project](https://junglewise.ai/threats/vendors/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

  ```sh
  # 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

- [https://github.com/netty/netty-incubator-codec-ohttp/security/advisories/GHSA-vmr9-j6wf-pmh2](https://github.com/netty/netty-incubator-codec-ohttp/security/advisories/GHSA-vmr9-j6wf-pmh2)
- [https://github.com/netty/netty-incubator-codec-ohttp/releases/tag/netty-incubator-codec-parent-ohttp-0.0.23.Final](https://github.com/netty/netty-incubator-codec-ohttp/releases/tag/netty-incubator-codec-parent-ohttp-0.0.23.Final)
- [https://api.github.com/repos/netty/netty-incubator-codec-ohttp/security-advisories/GHSA-vmr9-j6wf-pmh2](https://api.github.com/repos/netty/netty-incubator-codec-ohttp/security-advisories/GHSA-vmr9-j6wf-pmh2)

## Related threats

- [Netty Incubator OHTTP BinaryHttpParser infinite loop DoS](https://junglewise.ai/threats/cve-2026-63202-netty-incubator-ohttp-binaryhttpparser-infinite-loop-dos)
- [Netty OHTTP undetected stream truncation in OHttpVersionChunkDraft](https://junglewise.ai/threats/cve-2026-48480-netty-ohttp-undetected-stream-truncation-in)
- [Netty incubator-codec-ohttp predictable cryptographic key on failure](https://junglewise.ai/threats/cve-2026-41207-netty-incubator-codec-ohttp-predictable-cryptographic-key-on)
- [BoringSSLAEADContext in Netty Repeats Nonces](https://junglewise.ai/threats/cve-2024-36121-boringsslaeadcontext-in-netty-repeats-nonces)