The crypt(3) function performs password hashing with additional code added to deter key search attempts.
II. Problem Description
There is a programming error in the DES implementation used in crypt() when handling input which contains characters that can not be represented with 7-bit ASCII.
When the input contains characters with only the most significant bit set (0x80), that character and all characters after it will be ignored.
For a workaround and solution, check out the security advisory: FreeBSD-SA-12:02.crypt