CVE-2026-119078

Name of the Vulnerable Software and Affected Versions Apache Commons Codec versions 1.16.0 through 1.22.x

Description The doFinalize() function in the Blake3 class is stateless, meaning it does not change the hash state when called. Consequently, consecutive calls to this function without providing additional input return identical bytes. This contradicts the original documentation, which suggested that subsequent calls would produce different outputs. Applications using this function for key derivation, such as the example provided in the Javadoc, will derive identical keys, resulting in a loss of key separation.

Recommendations For versions 1.16.0 through 1.22.x, derive multiple keys by requesting the total combined length in a single doFinalize() call and then splitting the resulting output. As a temporary mitigation, avoid calling the doFinalize() function more than once on a single Blake3 instance if unique outputs are expected.