CVE-2026-41207: netty netty-incubator-codec-ohttp Use of Insufficiently Random Values

Vulnerability summary

CVE-2026-41207 is a medium (CVSS 6.9) Use of Insufficiently Random Values vulnerability in netty netty-incubator-codec-ohttp. EPSS estimates a 0.32% chance of exploitation in the next 30 days, higher than 23.8% of scored vulnerabilities.

Timeline

1. 04-06-2026
   PublishedVulnerability first disclosed.
2. 08-06-2026
   Last modifiedVulnerability information updated.

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.

• CWE-330Use of Insufficiently Random ValuesThe product uses insufficiently random numbers or values in a security context that depends on unpredictable numbers.