Recent reports show users who have upgraded to the new Mac OS X Lion operating system may need to fortify their login passwords to avoid security threats and serious Mac repair.

Computer researcher and blogger Patrick Dunstan wrote that a flaw in the operating system's design can allow non-authorized users to change a victim's password without verifying their true identity through its Terminal app.

In previous versions of Mac operating systems, users are asked to first input their current password before changing it. In Mac OS X Lion, that requirement has been removed, which means users could hypothetically have their password changed and be locked out of their own computer.

Additionally, a second flaw gives hackers greater access to hash data, which they can then use to identify a user's password.

It's expected Apple will reveal countermeasures that would provide greater security, but in the meantime, users need to ensure they exercise secure computer habits:

1. Develop a very strong password – In the case of the exposed hash data, a more complicated password can be difficult to crack. Users should disable automatic login and require their computer to ask for a password when turning on or returning from a screensaver.
2. Manage user accounts and access – Users should remove any frivolous accounts (such as a guest account) and avoid granting anyone remote access to their computer. They should also never leave their computer unattended in a public area.
3. Limit permissions for non-administrator accounts – Through parental controls, users can restrict other accounts' access to certain tools, including Terminal. Non-administrator accounts likely do not need to be able to change critical computer information, and limiting their capabilities may prevent a future call to a Washington, D.C. Mac repair specialist.