UBTU-20-010070 - The Ubuntu operating system must prohibit password reuse for a minimum of five generations.

Information

Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks. If the information system or application allows the user to consecutively reuse their password when that password has exceeded its defined lifetime, the end result is a password that is not changed as per policy requirements.

Satisfies: SRG-OS-000077-GPOS-00045, SRG-OS-000073-GPOS-00041

Solution

Configure the Ubuntu operating system to prevent passwords from being reused for a minimum of five generations.

Add or modify the 'remember' parameter value to the following line in '/etc/pam.d/common-password' file:

password [success=1 default=ignore] pam_unix.so obscure sha512 shadow remember=5 rounds=5000

See Also

https://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_CAN_Ubuntu_20-04_LTS_V1R10_STIG.zip

Item Details

Category: IDENTIFICATION AND AUTHENTICATION

References: 800-53|IA-5(1)(c), 800-53|IA-5(1)(e), CAT|III, CCI|CCI-000196, CCI|CCI-000200, Rule-ID|SV-238234r832945_rule, STIG-ID|UBTU-20-010070, Vuln-ID|V-238234

Plugin: Unix

Control ID: 9d2ae8946079166fc61d08886a27cf5141197eaa7092a72e70296d750d1ee036