Authentication fails. Restart vasd or doing a vastool flush fixes system.
Passwordless logins were triggering initgroup_dyn calls. However anything that calls getgroups could trigger this defect. For example: root su'ing to the account, or cron kicking off more than 4 cronjobs at once. Even a lot of id -a <user>
Product Defect: 702985. Fixed in 126.96.36.19964 and up.