What is an Attack Surface? Understanding Attack Surface Management (ASM) and Monitoring

Attack Surface Management or ASM is an emerging priority for IT-driven businesses aiming to complement their existing security testing and monitoring. It’s the process of continuous asset discovery, inventory, classification, and monitoring of a company’s technical architecture.

The ASM meaning is similar to asset discovery and management, however, it involves considering the vulnerability from cybercriminals’ perspectives. In this blog, we explore how effective attack surface management can prevent cyberattacks by securing sprawling assets and resources.

What is an Attack Surface?

An attack surface is a set of points on the boundary of an IT infrastructure that assists a company to discover, prioritize, and remediate vulnerabilities before cybercriminals exploit them. It’s categorized as follows:

Digital Attack Surface

This covers the entire IT network and software environment, including applications, codes, ports, and other entry and exit points.

Physical Attack Surface

Encompasses the company’s endpoint devices like desktop systems, laptops, mobile devices, and USBs.

Social Engineering Attack Surface

Social engineering tactics take advantage of careless and vulnerable user behaviours. The common attacks attempted using this technique are phishing, malware injection and typosquatting.

What is Attack Surface Management?

Attack surface management is the continuous monitoring and caution required to alleviate both present and future cyber threats. It covers all risk assessments, security controls, and security measures that together monitor and shield the attack surface to minimize the chances of cybercriminals exploiting system loopholes. 

Attack surface management tools detect vulnerability sets so that developers and cybersecurity experts are aware of the potential risks. The team members then take requisite actions to mitigate cyberattacks.

External Attack Surface Management or EASM is a new term that’s used interchangeably with ASM, however, the two aren’t the same. EASM is specifically for vulnerabilities and risks associated with external or internet-facing IT assets of a company. As stated above, these fall under the category of the digital attack surface. EASM doesn’t include physical attack surface and social engineering attack surface.

Attack surface management reduces cyber threats stemming from:

  • Legacy, IoT, and shadow IT assets
  • Careless user behaviour
  • Outdated and unpatched software and application
  • Unknown open-source software
  • Large-scale attacks on your domain
  • Intellectual property infringement
  • Vendor managed assets

How does Attack Surface Management Work?

The ASM process is split up into four core steps: 

  1. Asset discovery
  2. Classification, analysis and prioritization
  3. Remediation
  4. Monitoring

These are automated with the help of attack surface management tools as the cybersecurity team should have a real-time update of exposed assets.

Asset Discovery

Asset discovery is done using automated tools that continuously scan for security vulnerabilities in internet-facing hardware, software, and cloud assets. These assets include:

  • Known Assets: All IT infrastructure under the organization’s direct access and control, including routers, devices, IoT devices, websites, and proprietary data.
  • Unknown Assets: This includes all inventoried assets using network resources without the IT team’s knowledge and consent.  
  • Third-Party or Vendor Assets: These are the assets that the organization uses as a part of IT infrastructure or digital supply chain but doesn’t own it. These include SaaS applications, APIs, and public cloud assets.
  • Subsidiary Assets: This refers to a list of known, unknown or third-party assets belonging to networks of an organization’s subsidiary companies. 
  • Malicious or Rogue Assets: These are assets developed or stolen by cybercriminals to attack a company through data breaching or impersonation hits. 

Classification, Analysis, and Prioritization

Post asset discovery, they are inventoried by identity, IP address, ownership, and links to other assets. They are assessed for the exposure they have and threats they can impose.

After this, the system loopholes are prioritized for remediation on the basis of data accumulated from threat intelligence feeds, information collected during classification, and results of security risk management activities.


Remediation is actioned by priority order and involves:

  • Implementing adequate security control protocols for the asset in question. This can be debugging application code, updating the system and using stronger data encryption.
  • Aligning previously unknown assets under supervision.

The remediation process may also include using broader and cross-asset tactics like using the principle of least privilege, allowlisting, blocklisting, or multi-factor authentication.


Every IT system is prone to have vulnerabilities that hackers can exploit so both inventoried and existing assets are continuously monitored. This gives a heads up to security teams who can then patch them before cybercriminals can take advantage of these loopholes.

Attack Surface Management vs Vulnerability Management

The main difference between attack surface management and vulnerability management is the overall security scope encompassed within an IT structure. ASM has a wider environment under observation compared to vulnerability management, which is only concerned with the immediate impact of a vulnerable asset. 

Vulnerability management is a subset of attack surface management and is restricted to particular weak assets within a network and deals with code-based scans. 

Attack Surface Management vs Attack Vector

To combat cyber threats and achieve threat intelligence, it’s important to know about attack surface management vs attack vectors. 

What is an Attack Vector?

Attack vectors are techniques adopted by cybercriminals to gain unauthorized access to systems or accounts to steal or intercept data. These are categorized as- passive attack vectors and active attack vectors.

Passive attack vectors involve the exploitation of vulnerabilities without hampering systems’ resources and performances. These include eavesdropping tactics like session hijacking, port scanning and traffic analysis.

Active attack vectors involve the exploitation of vulnerabilities in ways that affect systems’ operating capacity. These include ransomware attacks, SQL injection attacks and DDoS attacks.

Difference Between Attack Surface and Attack Vectors

In simpler terms, the attack surface is the accumulation of all the vulnerabilities a cybercriminal can exploit with malicious intent. An attack vector is a technique that they use to exploit vulnerabilities in an IT infrastructure. 

Vulnerability testers map the attack surface to get a wider view of all the potential risks associated with IT architecture. Evaluating individual attack vectors gives an idea of what needs to be fixed or reinforced.

How Can Red Sift Help Business With Attack Surface Management and Monitoring?

Sharing similarities with Attack Surface Management, Hardenize by Red Sift offers a Continuous Threat Exposure Management (CTEM) methodology to provide businesses with automated asset discovery and continuous monitoring of their network for vulnerabilities. We notify you about expiring certificates to avoid downtime while also monitoring the certificates of third-party vendors associated with you. 

Hardenize enables business owners to get direct and full control over known and unknown vulnerabilities affecting their internet-facing assets across emails, domain names, and websites. Get a free analysis of your attack surface today by talking to our experts.

*Subject to availability


Red Sift

24 May. 2023



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