Privilege escalation is an attack technique that gives threat actors unauthorized access to higher-level permissions within a network or system. Granting malicious insiders higher permissions enables them to launch attacks, disable security policies, and cover their tracks more successfully. 

How privilege escalation works 

Most privilege escalation attacks rely on exploiting a vulnerability that allows a threat actor to compromise multiple assets or applications on a network. This behavior is closely related to lateral movement, which describes the process of gaining deeper, broader access to networks while looking for high-value data to modify, exfiltrate, or destroy. 

Most regular users are unaware of their permissions and privilege limitations — until they come across an asset or file they can’t access. A legitimate user may request access authorization for such a file, but a malicious one will try to gain access in secret. 

If threat actors are successful in their attempts to escalate privileges, they gain much more control over the system they are trying to exploit. This makes it much easier for them to launch highly sophisticated cyberattacks and make them difficult or impossible to defend against. 

There are two types of privilege escalation: 

• Vertical privilege escalation involves threat actors elevating their access from a lower level to a higher level. This gives them greater control over the system and allows them to make changes they would not otherwise be able to make. 

• Horizontal privilege escalation involves gaining access to resources or permissions at their current privilege level. These privileges may not grant additional capabilities, but they expand what the compromised account can do.

The main difference between these two types of privilege escalation is the attacker’s ultimate objective. Vertical escalation may indicate preparation for a complex cyberattack, while horizontal escalation may grant access to a specific file or asset the threat actor is looking for. 

How to prevent privilege escalation attacks 

There are several things security lakers can do to prevent threat actors from carrying out privilege escalation attacks: 

• Maintain a strict patch management strategy. Keeping systems up-to-date with the latest security patches prevents hackers from exploiting known vulnerabilities to escalate their privileges. 

• Deploy multi-layered authentication methods. Strong passwords are vital to preventative security, but they need support from robust multi-factor authentication (MFA) methods as well. 

• Apply the principle of least privilege. Limit user account permissions strictly to the assets and applications they need for their role. Avoid granting excessive permissions to any single account. 

• Segment networks with zero trust security in mind. The more segmented your network is, the harder it will be for threat actors to escalate their privileges and conduct lateral movement. Microsegmentation takes the concept even further, establishing small network segments for individual assets and applications. 

• Restrict Sudo rights. Sudo stands for “SuperUser Do”, granting complete control to users who have permission to run it. Linux, macOS, and now Windows all have some version of Sudo command line functionality. In most cases, it should be heavily restricted or disabled entirely.  

How to detect privilege escalation attacks 

Prevention-based security controls are not enough to fully mitigate the risk of privilege escalation. They should be complemented by a robust set of detection-based technologies and solutions. 

• Analyze system logs for unusual login activity. Your Security Information and Event Management (SIEM) platform can identify telltale signs of privilege escalation, like repeatedly failed login attempts or the use of unusual console commands. 

• Deploy behavioral monitoring technology. User Entity and Behavioral Analytics (UEBA) takes your SIEM one step further, enhancing insights with behavioral monitoring that tells you when authorized users are behaving abnormally. 

• Monitor credential usage for signs of compromise. Password monitoring solutions can warn you when users change passwords without authorization, or when an unusual volume of credential changes happen in a short time frame. 

• Invest in Dark Web monitoring. Hackers may carry out data breaches to gain access to login credentials they can sell on the Dark Web. If one of your employees’ credentials are exposed, they represent a much higher level of insider risk. 

5 attack vectors cybercriminals use to escalate privileges 

Threat actors may use multiple methods to escalate privileges and gain a firmer foothold on their target’s networks. Some of the most common methods they use involve leveraging misconfigurations, stealing user credentials, exploiting vulnerabilities, conducting social engineering attacks, or installing malware. 

1. Exploiting misconfigurations 

Misconfigured infrastructure can lead to privilege escalation attacks. When system administrators accidentally leave configuration errors in the environment, it provides threat actors with the opportunity to compromise privileged user accounts and gain more control. 

2. Credential-based attacks 

Attackers may take advantage of user accounts with weak passwords or steal valid credentials using keylogging or pass-the-hash attacks. They may target users with high-level permissions, take over their accounts, and then grant themselves the privileges they need to carry out an attack. 

3. Exploiting known vulnerabilities 

If your organization doesn’t have a robust patch management policy, threat actors may be able to leverage vulnerabilities in unpatched software. These are often widely known because software vendors release changelogs with each new update — and those changelogs contain all the information hackers need to know. 

4. Social engineering 

Attackers may trick employees, partners, or other human users into giving up important information about privileged user accounts. Even small bits of seemingly unimportant information can help hackers conduct these types of attacks. 

5. Malware 

Malware attacks can result in privilege escalation when deployed on targeted systems. An attacker may gain initial access to an asset and then deploy a malicious payload that escalates their ability to control it, resulting in a privilege escalation attack. 

Deploy robust, scalable protection against insider threats 

To adequately protect against insider risk, security teams need to implement technical capabilities supported by on-demand specialist talent. SIEM platforms must be enhanced with behavioral analytics and ample access to low-cost storage — without compromising observability. 

This requires a multi-layered threat defense that adheres to the SOC Visibility Triad, providing unlimited visibility and control to incident response teams. Supporting those teams with reputable managed detection and response capabilities blocks attackers from leveraging vulnerabilities and escalating permissions to execute attacks.