Title

AIX must prohibit password reuse for a minimum of five generations. (Cat II impact)

Discussion

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.

Check Content

From the command prompt, run the following command to check the system default "histsize" attribute value: # lssec -f /etc/security/user -s default -a histsize default histsize=5 If the default "histsize" value is not set, or its value is less than "5", this is a finding. From the command prompt, run the following command to check "histsize" attribute value for all accounts: # lsuser -a histsize ALL root histsize=5 user1 histsize=5 user2 histsize=5 user3 histsize=6 If any user does not have "histsize" set, or its "histsize" value is less than "5", this is a finding.

Fix Text

From the command prompt, run the following command to set "histsize=5" for the default stanza in "/etc/security/user": # chsec -f /etc/security/user -s default -a histsize=5 For each user who has "histsize" value less than "5", set its "histsize" to "5" by running the following command from command prompt: # chsec -f /etc/security/user -s [user_name] -a histsize=5

Additional Identifiers

Rule ID: SV-215224r508663_rule

Vulnerability ID: V-215224

Group Title: SRG-OS-000077-GPOS-00045

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.