Summary
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.
Impact
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
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Frequently Asked Questions
- What is CVE-2026-54251? CVE-2026-54251 is a high-severity security vulnerability in io.netty.incubator:netty-incubator-codec-ohttp (maven), affecting versions < 0.0.23.Final. It is fixed in 0.0.23.Final.
- Which versions of io.netty.incubator:netty-incubator-codec-ohttp are affected by CVE-2026-54251? io.netty.incubator:netty-incubator-codec-ohttp (maven) versions < 0.0.23.Final is affected.
- Is there a fix for CVE-2026-54251? Yes. CVE-2026-54251 is fixed in 0.0.23.Final. Upgrade to this version or later.
- Is CVE-2026-54251 exploitable, and should I be worried? Whether CVE-2026-54251 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2026-54251 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2026-54251? Upgrade
io.netty.incubator:netty-incubator-codec-ohttpto 0.0.23.Final or later.