Computer security is a field where the goal posts are constantly moving, as malware morphs in an attempt to outsmart the defences you put in place. While security professionals have recognised for a long time that unwanted software, often in the form of Trojans and worms usually installed by users when tricked by some form of social engineering, presents the biggest risk to security, it’s only now that compliance mandates are catching up and are being developed based on real-world attack data.
Australia’s Department of Defence Intelligence Agency produced a report of mitigation strategies using research on attacks carried out in 2010, and later updated in 2011. It concluded that 85 per cent of attacks could have been prevented if its top 4 recommendations had been followed. These top 4 recommendations are known as the security ‘sweet spot’:
* use application whitelisting to help prevent malicious software and other unapproved programs from running.
* patch applications such as PDF readers, Microsoft Office, Java, Flash Player and web browsers.
* patch operating system vulnerabilities.
* minimize the number of users with administrative privileges.
“The Australian government has already implemented the report’s recommended strategies to good effect, allowing only whitelisted applications to run and removing administrative privileges wherever possible,” said Paul Kenyon, COO at Avecto. “Application whitelisting and privilege management can help avoid the inconvenient trade-off in usability that security measures often impose. This way IT administrators can remove administrative privileges and block restricted applications while ensuring that users have the flexibility to work as required.”
The UK government’s Public Services Network (PSN) has a new set of standards that replaced the Government Secure Intranet Code of Connection (GSi CoCo) in November 2012. Based on ISO 27001, the new controls are outcome-based so that government departments can comply how they see fit rather than check a list of technical requirements. The PSN Standards list of configuration controls includes preventing the execution of unauthorized software, best achieved through application whitelisting, and explicitly states that administrative privileges should be removed where possible.
Not all the latest security mandates are coming from the government. The SANS institute has created its own list of 20 controls in consortium with government and industry bodies. As expected, included in the controls is the removal of administrative privileges, and though application whitelisting isn’t explicitly mentioned, the secure configuration of workstations and servers is a key priority.
“Most current security mandates imply that least privilege should be deployed rather than state it explicitly. But as the importance of least privilege becomes better understood, that’s starting to change. Whether you need to comply with current or future mandates, least privilege security is a defence strategy that cannot be ignored if you need to meet basic compliance requirements,” said Kenyon.