CVE-2026-41207: netty-incubator-codec-ohttp's HPKEContext operations may produce empty byte[] on failures

Severity: medium (CVSS 5.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-06-04 · updated 2026-07-22
Weakness: CWE-330

Description

The netty incubator codec.bhttp is a java language binary http parser. Prior to version 0.0.21.Final, HKDF_expand returns non-NULL on failure. The byte[] is filled with zeros and has no way to distinguish success from failure. Since this output is used as HKDF key material for the response AEAD, a failure silently produces an all-zero key. When EVP_HPKE_CTX_export fails it also returns an empty byte[] array filled with zeros. This byte[] feeds directly into OHttpCrypto.createResponseAEAD(...). A silent all-zero export secret would produce a deterministic, attacker-predictable AEAD key. Version 0.0.21.Final patches the issue.

Affected products

netty-incubator-codec-ohttp: before 0.0.21 — fixed in 0.0.21

How to fix

Upgrade to a fixed version: netty-incubator-codec-ohttp 0.0.21. Check the vendor advisory for mitigations.

References

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