APR-util versions 1.6.3 (and earlier) function apr_password_validate() was not constant-time with...

APR-util versions 1.6.3 (and earlier) function apr_password_validate() was not constant-time with regards to hashes or passwords comparisons, potentially leaking their content via a side channel timing attack particularly on platforms without crypt() such as  Windows, BeOS, NetWare, or Android.

Users are recommended to upgrade to version 1.6.4, which fixes this issue.