What Is Attack Surface Management (ASM)

Why Is It Important to Know Your Attack Surface?

With every passing year, the potential of cyberattacks is expanding at a rapid pace. Just in the first quarter of 2023, the global weekly cyberattacks increased by 7%. As organizations are embracing technological advancements and digitalization, their attack surface is also expanding. Today, cybercriminals have plenty of entry points to exploit. Therefore, it has become crucial for organizations to improve their attack surface visibility to have more effective protection. This is where attack surface management (ASM) comes into play. This article will explore all about attack surface management (ASM), including its importance, working principle, and benefits.

What Is Attack Surface Management (ASM)?

Attack surface management (ASM) is the process of continuous discovery, classification, analysis, remediation, and monitoring of an organization’s potential attack vectors or cybersecurity vulnerabilities that make up its attack surface.

Attack surface implies all attack vectors that attackers can exploit to breach through security defenses and gain unauthorized access to an organization’s IT infrastructure. It can be servers, hardware equipment, SaaS applications, cloud services, or any other attack vector that can serve as an entry point.

Attack surface management (ASM) is performed from the attacker’s perspective, identifying and exploiting all entry points that attackers can use. Moreover, the methods and resources used in it also resemble those used by attackers. This helps organizations to identify and assess risks to known and unknown assets before attackers discover them.

Why Is It Important to Know Your Attack Surface?

The attack surface of organizations has increased exponentially for the past few years due to digital transformation, cloud adoption, and remote working culture. With more dynamic and distributed company operations, the digital footprints have become bigger. As per the State of Attack Surface Management 2022 report by Randori, 67% of organizations witnessed an expansion in attack surfaces during the past 12 months.

When the attack surface has increased, it means an organization has more connected assets, including the ones it is unaware of. This means there are many more entry points for attackers now than before. In fact, Industry analysts at Gartner declared attack surface expansion as the top security and risk management priority in 2022 for CISOs.

Therefore, it is very crucial for organizations to know their attack surface, especially for those who are embracing digital transformation and technological advancements. The importance is also evident from two real-world examples.

SolarWinds and Log4J supply chain attacks were successful because there was an assumption that third-party vendors were secure. Similarly, the Colonial Pipeline ransomware attack was made by exploiting remote services like remote desktop protocol (RDP), remote desktop web (RDWeb), or Citrix. The attacks were successful in these examples because organizations failed to monitor and assess their complete attack surfaces.

When an organization expands its digital landscape, it becomes complicated to have complete visibility of all its IT assets. Therefore, a comprehensive attack surface management can lead to better monitoring, classification, assessment, and remediation.

How Does Attack Surface Management (ASM) Work?

ASM aims to empower security teams to have a current and complete inventory of assets and to ensure a proactive response to high-priority threats and vulnerabilities. So, ASM consists of five main processes. The details of each of those processes are as follows:

1. Asset Discovery
The first stage in ASM is identifying all internal and external assets that can be entry points to an organization’s IT infrastructure. The assets can be:

Known assets: These include all assets known to an organization, such as routers, servers, IoT devices, cloud applications, workstations, databases, websites, etc.
Unknown assets: These include shadow assets that are using network resources without the knowledge or approval of the IT security team, such as a new mobile device, illegal downloads, unauthorized cloud services, etc.
Vendor or Third–party Assets: These include assets that are not owned by the organization but are included in its IT infrastructure, such as APIs, public cloud assets, SaaS applications, etc.
Compromised or Malicious Assets: These include assets that are either stolen or created by threat actors to attack an organization, such as compromised data of an organization shared on the dark web, a phishing website reflecting the organization’s brand, etc.

In short, this ASM stage involves identifying all the assets that are linked with the organization and can be used to penetrate the network.

2. Classification
Once the assets are identified, the next stage is to classify them. It involves labeling the assets based on their properties, technical characteristics, type, compliance requirements, ownership, business criticality, potential vulnerabilities, etc. In short, this ASM stage is about enriching assets with information and creating a resourceful asset inventory.

3. Prioritization
It is not possible for any organization to fix all the attack vectors against all assets. So, once the assets are classified, they are analyzed to evaluate the exposure level, the exposure causes, and the type of attacks executable through those exposures. The security team can even give security ratings or risk scores to better reflect the exposure potential each asset holds.

After thorough analysis, the attack vectors are prioritized so that most potential vulnerabilities or exploitable assets are fixed first. In short, this ASM stage is to create one comprehensive list of vulnerabilities for all the known/unknown assets.

4. Remediation
Remediation is an important stage in ASM that involves remediating the vulnerabilities/assets based on the prioritized list. The remediation process can involve:

Debugging application code
Applying OS or software patches
Eliminating rogue assets
Setting security standards for shadow assets
Fixing compliance issues
Implementing data encryption
And many more.

In short, this ASM stage is about implementing security measures to mitigate vulnerabilities and attack vectors.

5. Continuous Monitoring
Since the attack surface of organizations is continuously evolving with newly connected assets or changes in existing assets, the need for continuous monitoring becomes essential. Therefore, this ASM stage continuously monitors and assesses vulnerabilities and attack vectors in real-time. This way, security teams can get timely alerts of new potential vulnerabilities, leading to enhanced protection.

Key Benefits of Attack Surface Management (ASM)

By now, we have learned what ASM is all about and its importance in the modern business landscape. So, now let’s shed light on what key benefits organizations can get with ASM. Below are the key benefits of deploying ASM:

Comprehensive visibility of all assets
Continuous monitoring of endpoints to identify new vulnerabilities
Improved mitigation from real-world threats
Increased overall security posture of the whole infrastructure, including ICS/SCADA systems and similar others
Improved assessment of the security of third-party vendors or suppliers
Minimized risk of disruptions

Overall, attack surface management (ASM) serves as an ideal complement to existing cybersecurity measures, providing organizations with comprehensive visibility, continuous monitoring, and improved mitigation capabilities against real-world threats.