Throughout the world, from Australia’s Bureau of Meteorology to Bangladesh Bank and SWIFT, organisations continue to fall victim to devastating cyber attacks. Conducted to cause disruption, send a message or for financial gain, the attacks cannot be prevented by traditional antivirus software or other signature-based tools.
Even if the attacks are detected, it’s often too late to stop data loss or business disruption. According the latest Mandiant M-Trends report, while the median number of days attackers were present on a victim’s network before being discovered dropped to 146 days (down from 205 days in 2014), the company warned that breaches often still go undetected for years. More effective, proactive security safeguards require a solid understanding of the attack lifecycle. The stages are:
Stage 1. Acquire credentials: The attacker acquires user credentials with standard permissions – or privileges - that exist within an organisation’s network. This is simple if the attacker is a trusted insider like an employee or contractor, or if those credentials were secured through a targeted phishing attack from the outside.
Stage 2: Escalate privileges: This can be achieved by increasing the privileges available on an existing account or by acquiring access to another account with greater privileges. The first can be done by exploiting operating system vulnerabilities, while the second can occur through lateral movement where attackers can ‘collect’ privileges as they move about the network.
Stage 3: Acquire access to the targeted assets: Reconnaissance is then performed using the escalated privileges. The purpose is to identify one or more accounts or assets that should get the attacker closer to their goal.
Stage 4: Use whatever this access has gained: If the goal is compromising sensitive data, once located it can be exfiltrated from the organisation without detection. If the goal is disruption, it can be achieved byattacking other internal IT assets to gain complete control over the network.
The power of privilege
The entire lifecycle of a cyber attack relies on gaining access to privileged accounts within the target organisation. These accounts – are often referred to as the keys to the IT kingdom because they have higher privileges than standard user accounts, such as the ability to administer operating systems, applications, and data.
Privileged accounts are prized by advanced attackers because a single account often provides administrative privileges on multiple assets. This allows an attack to quickly progress from asset to asset within an enterprise, compromising each along the way until the target is reached.
An effective approach to breaking the attack lifecycle is to make it much more difficult for attackers to obtain privileged account credentials. This can be achieved through privileged account security best practices such as:
·Securely store privileged credentials: Privileged account credentials, including passwords and SSH keys, should be safeguarded in a secure, centralised vault. This makes them far less susceptible to compromise than credentials that are stored insecurely throughout the network or on individual machines.
·Automatic rotation of privileged credentials: When passwords and credentials are unchanged, they can remain unmonitored and be reused for extended periods of time. For example, former employees may be able to access accounts long after they have left an organisation. An organisation can significantly decrease the likelihood of a damaging breach by using unique privileged credentials that are regularly rotated.
·Isolation of privileged account sessions: Temporary employees, contractors and third-party vendors often need access to systems to do their jobs. To help protect the assets they access from unintentional or malicious damage, organisations can secure privileged sessions by isolating session activity in a secure environment. Secure session isolation can prevent malware from spreading to critical systems from a single desktop.
·Policy restrictions: While administrative accounts typically grant full, unfettered access to systems and databases, it is prudent to take a more granular approach to granting privileges. The concept of least privileges means granting users only the access they need – nothing more, and nothing less. This might involve specifying which commands each user can or cannot perform on each asset, controlling and monitoring which applications are permitted to run, and setting days of the week and times of the day when each user can have access to certain systems.
The importance of continuous monitoring
In addition to having multiple layers of defence against attacks and intrusions, constant monitoring is also critical. The goal is to be alerted in real time to an attack in-progress, stop it from proceeding any further, and prevent continued access to assets that were already compromised. The earlier in the attack lifecycle that the attack can be detected, the sooner that security teams can respond and prevent further damage.
Key to more rapid threat detection is focusing on privileged accounts, which are at the heart of the attack lifecycle. By implementing privileged account security best practices, organisations have the ability to implement and maintain proactive security strategies focused on promoting business continuity.