# CVE-2026-54251

## Summary

- **CVE ID:** CVE-2026-54251
- **Severity:** HIGH
- **CVSS Score:** 8.7 (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)
- **CWE:** CWE-664
- **Published:** Sep 15, 2026
- **Last Modified:** Sep 15, 2026

## 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.

## Affected Products

- netty — netty-incubator-codec-ohttp (< 0.0.23.Final)
- io.netty.incubator — netty-incubator-codec-ohttp (< 0.0.23.Final)

## References

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

## Exploitation Prediction (EPSS)

- **EPSS Score:** 0.29%
- **EPSS Percentile:** 21.8

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_Exported from OnDuty AI Vulnerability Intelligence on 2026-09-18._