sudo authentication bypass when clock is reset

Rod Simmons, March 7th, 2013

A recent discovery by a German researcher, Marco Schoepl, found that it is possible for a user to bypass sudo authentication by resetting the clock. To read more about this vulnerability see the articles on and What we have found is that many highly secure customers have already adopted the timestamp_timeout=0 setting which will bypass the default 5 minute password reentry interval and requires authentication for each command.

You could consider this vulnerability a configuration issue but it does highlight a general need to use a solution that provides an option for IO logging. Our PowerBroker Unix & Linux solution is a Command Control solution that also provides a method to perform IO Logging so you can replay a user’s entire session, after all, once they have elevated permissions it becomes vital to securely log the actions of that user.

It is always possible to have a configuration issue in any security system due to flexibility and general complexity of building a secure system. The key principle is to only delegate the rights needed and perform IO logging along with multi-factor authentication as an additional safety measure.

If you require a Sudo replacement, or want to implement greater controls where compliance requires it, PowerBroker Servers can help. Learn more about PowerBroker Servers now!