In general, we recommend:
patching applications & operating systems
limiting the number of users with administrative privileges
using multifactor authentication for critical systems
using strong passwords/passphrases.
In addition, we advise businesses to implement the Strategies to Mitigating Cyber Security Incidents released by the Australian Signals Directorate. The strategies are a prioritised list of practical actions organisations can take to make their computers more secure. The advantage of this guidance is that it is customisable to each organisation based on their risk profile and the threats they are most concerned about.
For detailed and time sensitive information on action that can be taken in regard to vulnerabilities and/or mitigation strategies – eg a security flaw or vulnerability in a particular product, please see advisories.
For advice on how to better protect information and/or systems, please see guidance.