CVE-2026-41207: netty-incubator-codec-ohttp's HPKEContext operations may produce empty byte[] on failures
HKDFexpand: 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 EVPHPKECTXexport 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.
Other sources
The netty incubator codec.bhttp is a java language binary http parser. Prior to version 0.0.21.Final, HKDFexpand 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 EVPHPKECTXexport 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.
— MITRE
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
maven/io.netty.incubator:netty-incubator-codec-ohttpto a version that resolves this vulnerability.Fixed in 0.0.21.Final - Upgrade
Upgrade
netty-incubator-codec-bhttp / netty-incubator-codec-ohttp (OHttpCrypto.createResponseAEAD / HPKEContext)to a version that resolves this vulnerability.Fixed in 0.0.21.Final - Operational
If you ever produced response AEAD keys using HKDF_expand output or HPKEContext export output that may have silently failed, rotate/recreate any affected keys and invalidate any derived artifacts created from those all-zero/empty byte[] values.
Event History
Frequently Asked Questions
What is the severity of CVE-2026-41207?
CVE-2026-41207 has a risk score of 52, indicating a moderate severity level.
How do I fix CVE-2026-41207?
To fix CVE-2026-41207, update the affected version of the maven/io.netty.incubator:netty-incubator-codec-ohttp library to the latest release that addresses this vulnerability.
What are the potential impacts of CVE-2026-41207?
CVE-2026-41207 could lead to the generation of all-zero keys due to silent failures, compromising the security of cryptographic operations.
Which software is affected by CVE-2026-41207?
CVE-2026-41207 affects maven/io.netty.incubator:netty-incubator-codec-ohttp and its implementations.
Is CVE-2026-41207 a zero-day vulnerability?
CVE-2026-41207 is not classified as a zero-day vulnerability, as it was published on May 26, 2026.