# Best Attack Surface Management Solutions for Business (2026)

Compare 7 attack surface management solutions, like Cortex Xpanse, Microsoft Defender EASM and CyCognito, on asset discovery, risk ranking and testing.

We pick every solution on this list [on merit](https://cybersectools.com/methodology#shortlist-order). Featured vendors that made the list are shown first.

Source: https://cybersectools.com/shortlists/best-attack-surface-solutions
Updated: 2026-11-01
Edition: Fall 2026.
Reviewed by Nika (Nikoloz) Kokhreidze, CybersecTools.

## Executive summary

As of November 2026, CybersecTools tracks 161 companies that sell exposure & vulnerability management solutions as their main business. External Attack Surface Management is part of that family. The largest groups are based in the United States, the United Kingdom and Israel. In the last 12 months they raised $545M across 31 funding rounds, 7 companies were acquired and 32 new companies started in the last two years.

From that field we chose seven solutions that find what your company exposes on the internet and tell you what to fix first. Cortex Xpanse leads for large companies that want internet-wide scanning plus automated playbooks to close exposures. Microsoft Defender EASM suits teams already on Microsoft that want discovery tied to Defender for Cloud. CyCognito fits teams that want discovery and active security testing in one product.

The main choice here is discovery alone versus discovery plus testing. Some products map your assets and flag known weak spots. Others also attack those assets safely to prove which exposures are real.

Testing cuts noise but adds cost and setup. If you mostly need an inventory you can trust, start with discovery and add testing later.

## How we evaluated

We looked at 175 external attack surface management solutions from 95 companies, and the 7 on this page made the cut. We combined our judgment from years of leading enterprise security programs with market data from [Mandos](https://mandos.io/data/companies?utm_source=cybersectools.com&utm_medium=shortlist), our market intelligence platform, and with the vendor and review pages listed under Sources at the end of this page. For customer feedback, we left out paid reviews, reviews by vendor staff or partners, review campaigns and anything older than two years, so you get an accurate view of what customers say.

Four traits mattered most: finding unknown assets from a few starting points, linking each asset to the right owner, ranking exposures so the urgent ones come first, and sending findings into the systems where fixes happen. We left out single-purpose utilities such as certificate or DNS watchers. The order follows how widely each product is used by teams like yours. Company momentum shows how the vendor itself is growing, so a market leader can rank first with a lower score.

Read the full method: https://cybersectools.com/methodology#why

## What is External Attack Surface Management

External attack surface management (EASM) finds every system your company exposes to the internet, including ones nobody remembers. It starts from a few domains or IP ranges, then maps websites, servers, cloud assets and subdomains the way an attacker would. It flags weak spots such as outdated software, open ports and misconfigured cloud services, and it keeps watching for changes every day.

For you, this matters because attackers scan the internet all day. A test server left online or a forgotten domain from an acquisition is often how they get in. You cannot protect assets you do not know you have.

### Compare External Attack Surface Management solutions

This analysis focuses on seven external attack surface management solutions. The table compares them on vendor, who each one is best for, deployment model and the NIST CSF functions they cover.

| # | Solution | Best for | Starting price | Deployment | Company size | NIST CSF functions |
| --- | --- | --- | --- | --- | --- | --- |
| 1 | [Palo Alto Networks Cortex Xpanse](https://cybersectools.com/tools/palo-alto-networks-cortex-xpanse) | Large companies wanting automated fixes for exposures | Contact sales | Cloud | Mid-Market to Enterprise | Identify, Protect, Detect |
| 2 | [Microsoft Defender EASM](https://cybersectools.com/tools/microsoft-defender-external-attack-surface-management) | Microsoft shops adding external asset discovery | From $0.01 per asset | Cloud | SMB to Enterprise | Identify, Detect |
| 3 | [Mandiant Attack Surface Management](https://cybersectools.com/tools/mandiant-attack-surface-management) | Teams wanting threat intel-backed exposure checks | Contact sales | Cloud | Mid-Market to Enterprise | Identify, Detect |
| 4 | [Censys Attack Surface Management](https://cybersectools.com/tools/censys-attack-surface-management) | Teams wanting broad internet data behind discovery | Contact sales | Cloud | Mid-Market to Enterprise | Identify, Detect |
| 5 | [CyCognito EASM Platform](https://cybersectools.com/tools/cycognito-easm-platform) | Teams wanting discovery plus active testing | Contact sales | Cloud | Mid-Market to Enterprise | Identify, Detect |
| 6 | [Bitsight External Attack Surface Management](https://cybersectools.com/tools/bitsight-external-attack-surface-management) | Teams reporting cyber risk to boards and insurers | Contact sales | Cloud | SMB to Enterprise | Govern, Identify |
| 7 | [Searchlight Exposure](https://cybersectools.com/tools/assetnote-attack-surface-management-tool) | Teams wanting hourly scans and zero-day warnings | Contact sales | Cloud | SMB to Enterprise | Identify, Detect |

Vendors change prices, so check before you buy.

**See every External Attack Surface Management solution we list**

The full External Attack Surface Management market, filtered by company size, deployment and NIST coverage.

[Browse External Attack Surface Management solutions →](https://cybersectools.com/categories/external-asm)

### 1. Palo Alto Networks Cortex Xpanse

**[Palo Alto Networks](https://mandos.io/data/companies/palo-alto-networks?utm_source=cybersectools.com&utm_medium=shortlist-md&utm_campaign=explore-in-mandos)**. Active attack surface mgmt solution for discovering & remediating unknown risks

Santa Clara, United States · Founded 2005 · Public company · Momentum 85/100 (Mandos)

Certifications: SOC 2, ISO 27001, FedRAMP, PCI DSS, HIPAA

**Best for:** Large companies wanting automated fixes for exposures

Product page: https://cybersectools.com/tools/palo-alto-networks-cortex-xpanse

#### At a glance

- Vendor: Palo Alto Networks
- Headquarters: Santa Clara, United States
- Founded: 2005
- Ownership: Public company (PANW)
- Deployment: Cloud
- Company size: Mid-Market, Enterprise
- NIST CSF: Identify, Protect, Detect
- Pricing: Contact sales

#### Our take

Cortex Xpanse scans the internet continuously to find unknown and unmanaged assets, including shadow cloud services. It uses supervised machine learning to map your attack surface and rank risk, and it runs automated playbooks to fix exposures without waiting on IT tickets. It also helps assess exposure to new zero-days and the security of companies you acquire.

It connects to AWS, Google Cloud, Azure, Microsoft Sentinel, Splunk, ServiceNow, Jira and Tenable.

It earns a place because it goes past listing exposures, since automated playbooks close them without a ticket, which suits a large company with a sprawling footprint. It fits mid-market and enterprise teams. Agree up front which fixes the playbooks may run on their own, because automatic changes to live assets need an owner.

#### Palo Alto Networks Cortex Xpanse main features

- Continuous internet-wide scanning of 500B+ ports daily
- Automated discovery of unknown and unmanaged assets
- Supervised machine learning for attack surface mapping
- Automated remediation playbooks
- Shadow cloud detection and elimination
- Zero-day vulnerability exposure assessment
- M&A security posture evaluation
- Real-time risk prioritization

#### Palo Alto Networks Cortex Xpanse main integrations

Amazon Web Services, Microsoft Sentinel, ServiceNow, Splunk, Google Cloud Platform, MS Azure, IBM QRadar, Jira Server, Tenable.io, Qualys VM, Rapid7 InsightVM, Venafi TPP

#### What customers say

Customers use Xpanse to map everything their company exposes on the internet, from domains and subnets to websites and cloud storage, and to keep that map current. The value they describe is finding assets nobody knew about, so the team can see and close external exposure before it becomes a problem.

#### Before you buy

Where it is strong:

- Automated playbooks that fix exposures without IT tickets
- Zero-day exposure checks across your attack surface
- Security review of companies you acquire

Ask in the demo:

- Run a discovery trial and compare the results with your current asset list
- Ask which playbooks run out of the box for your common exposures
- Check whether the dashboard can show the views your team needs

### 2. Microsoft Defender EASM

**[Microsoft](https://mandos.io/data/companies/microsoft?utm_source=cybersectools.com&utm_medium=shortlist-md&utm_campaign=explore-in-mandos)**. Discovers and monitors external-facing assets and vulnerabilities

Redmond, United States · Founded 1975 · Public company · Momentum 59/100 (Mandos)

Certifications: SOC 2, ISO 27001, FedRAMP, PCI DSS, HIPAA

**Best for:** Microsoft shops adding external asset discovery

Product page: https://cybersectools.com/tools/microsoft-defender-external-attack-surface-management

#### At a glance

- Vendor: Microsoft
- Headquarters: Redmond, United States
- Founded: 1975
- Ownership: Public company (MSFT)
- Deployment: Cloud
- Company size: SMB, Mid-Market, Enterprise
- NIST CSF: Identify, Detect
- Starting price: From $0.01 per asset

#### Our take

Microsoft Defender EASM keeps a live inventory of your internet-facing assets across cloud, SaaS and hybrid setups, including shadow IT. It flags vulnerabilities and misconfigurations, tracks OWASP Top 10 issues and ranks exposures on dashboards. You can ask questions in plain language through Copilot in Azure, and bring discovered assets under management in Microsoft Defender for Cloud.

It belongs here if you already pay for Microsoft security, because discovered assets can move into Defender for Cloud and Copilot in Azure turns plain questions into inventory searches. It fits companies from small to enterprise. Its features center on discovery and flagging, so ask whether you also need active testing to prove which exposures are real.

#### Microsoft Defender EASM main features

- Real-time inventory monitoring of external-facing resources
- Discovery of unmanaged resources and shadow IT
- Multi-cloud and hybrid environment visibility
- Vulnerability and misconfiguration detection
- Code-level discovery through global network mapping
- AI-driven asset risk insights through Copilot in Azure
- Natural language to inventory query conversion
- OWASP Top 10 vulnerability tracking

#### Microsoft Defender EASM main integrations

Microsoft Defender for Cloud, Microsoft Security Copilot, Microsoft Security Exposure Management, Copilot in Azure

#### What customers say

Sentiment: 17% positive · 50% mixed · 33% negative (from first-hand public reviews and comments, 2025 to 2026).
Most praised: Asset discovery.
Most criticized: Updates and fixes, Integrations.

Defender EASM is valued for finding internet-facing assets nobody knew about, and it keeps watching for new or changed exposures instead of relying on occasional manual checks. Expect some upfront work, because you have to confirm which discovered assets really belong to you. Longtime users also worry about where it is going, since it has changed little since launch and still runs apart from the main Defender portal, so it doesn't fit neatly with the rest of your Microsoft security work.

#### Before you buy

Where it is strong:

- Assets move into Microsoft Defender for Cloud for management
- Plain-language inventory search through Copilot in Azure
- OWASP Top 10 tracking on discovered web assets

Ask in the demo:

- Compare its vulnerability findings with your current scanner on the same assets
- Ask Microsoft for its roadmap, since users say it has changed little
- Model the cost for your full asset count before you commit

### 3. Google Mandiant Attack Surface Management

**[Google](https://mandos.io/data/companies/google?utm_source=cybersectools.com&utm_medium=shortlist-md&utm_campaign=explore-in-mandos)**. Discovers and monitors external internet assets for exposures and vulnerabilities

Mountain View, United States · Founded 1998 · Public company · Momentum 50/100 (Mandos)

Certifications: SOC 2, ISO 27001, FedRAMP, PCI DSS, HIPAA

**Best for:** Teams wanting threat intel-backed exposure checks

Product page: https://cybersectools.com/tools/mandiant-attack-surface-management

#### At a glance

- Vendor: Google
- Headquarters: Mountain View, United States
- Founded: 1998
- Ownership: Public company (GOOGL)
- Deployment: Cloud
- Company size: Mid-Market, Enterprise
- NIST CSF: Identify, Detect
- Pricing: Contact sales

#### Our take

Mandiant Attack Surface Management discovers your external assets from a few starting points such as domains, networks or SaaS accounts. It scans daily, weekly or on demand and identifies the technologies and services you run. Its active checks use benign payloads built from Mandiant threat intelligence to test whether an asset can really be exploited.

It sends daily summaries of new assets and connects to ServiceNow, Splunk Enterprise and Cortex XSOAR, plus cloud and DNS providers.

It earns a place because its checks test whether an exposure can be exploited, not only whether it exists. Role-based access for subsidiaries suits a group with several companies under one roof. Ask how often active checks will run on your assets, since that decides how fast a new exposure shows up.

#### Mandiant Attack Surface Management main features

- Continual automated external asset discovery
- Continuous monitoring with daily, weekly or on-demand scans
- Technology and service identification
- Outcome-based asset discovery
- Active asset checks
- Intel-informed active and passive checks
- Shadow IT identification
- Daily summaries of new assets and technologies

#### Mandiant Attack Surface Management main integrations

ServiceNow, Splunk Enterprise, Cortex XSOAR, Cloud providers, DNS providers

#### Before you buy

Where it is strong:

- Active checks built from Mandiant threat intelligence
- Subsidiary monitoring with role-based access control
- Daily summaries of new assets and technologies

Ask in the demo:

- Ask for customer references, since public reviews are thin
- Confirm how the product fits Google's current security offering
- Test active checks on a small scope before running them widely

### 4. Censys Attack Surface Management

**[Censys](https://mandos.io/data/companies/censys?utm_source=cybersectools.com&utm_medium=shortlist-md&utm_campaign=explore-in-mandos)**. Internet intelligence platform for asset discovery and attack surface mapping

Ann Arbor, United States · Founded 2017 · $198M raised · Momentum 81/100 (Mandos)

Certifications: SOC 2

**Best for:** Teams wanting broad internet data behind discovery

Product page: https://cybersectools.com/tools/censys-attack-surface-management

#### At a glance

- Vendor: Censys
- Headquarters: Ann Arbor, United States
- Founded: 2017
- Deployment: Cloud
- Company size: Mid-Market, Enterprise
- NIST CSF: Identify, Detect
- Pricing: Contact sales

#### Our take

Censys Attack Surface Management is built on Censys' continuously updated map of internet infrastructure. It discovers and monitors your internet-facing assets, finds cloud assets and shadow IT, ranks risk, and covers industrial control systems. It also supports risk checks of subsidiaries and acquisitions, and the same data helps with threat hunting.

It connects to AWS, Azure, Google Cloud, Microsoft Sentinel, Splunk, ServiceNow, Jira and Wiz.

It is on the list because discovery rests on a map of the whole internet that Censys keeps current, and the same data serves threat hunting, which suits a team that wants one source for both jobs. It fits mid-market and enterprise companies. Ask how it ranks risk for your assets, since a broad map is only as useful as the order it puts findings in.

#### Censys Attack Surface Management main features

- Continuous internet-wide scanning and mapping of global infrastructure
- Real-time discovery and monitoring of internet-facing assets
- Attack surface management with personalized risk prioritization
- Threat hunting capabilities for tracking adversary infrastructure
- Cloud asset discovery and shadow IT identification
- Critical infrastructure and ICS environment visibility
- Subsidiary and M&A cybersecurity posture assessment
- Highly-structured internet data with rich contextual intelligence

#### Censys Attack Surface Management main integrations

AWS, Microsoft Azure, Google Cloud Platform, Atlassian Jira, Cisco Webex Teams, Google Security Operations, Microsoft Sentinel, Microsoft Teams, Qualys VMDR, ServiceNow CMDB, ServiceNow ITSM, ServiceNow VR, Slack, Splunk, Tenable Vulnerability Management, Wiz

#### Before you buy

Where it is strong:

- Built on a continuously updated map of internet infrastructure
- Visibility into industrial control system exposure
- Connects to ServiceNow, Jira, Slack and Microsoft Teams

Ask in the demo:

- Ask for customer references, since public reviews are thin
- Check how findings are ranked and how much noise reaches your team
- Confirm which cloud accounts it can read assets from directly

**Alternatives to each solution on this list**

The closest External Attack Surface Management alternatives for every pick, matched on features and integrations.

[See External Attack Surface Management alternatives →](https://cybersectools.com/alternatives)

### 5. CyCognito EASM Platform

**[CyCognito](https://mandos.io/data/companies/cycognito?utm_source=cybersectools.com&utm_medium=shortlist-md&utm_campaign=explore-in-mandos)**. EASM platform that discovers, attributes, and actively validates external assets and risks

Palo Alto, United States · Founded 2017 · $153M raised · Momentum 43/100 (Mandos)

Certifications: SOC 2, ISO 27001

**Best for:** Teams wanting discovery plus active testing

Product page: https://cybersectools.com/tools/cycognito-easm-platform

#### At a glance

- Vendor: CyCognito
- Headquarters: Palo Alto, United States
- Founded: 2017
- Deployment: Cloud
- Company size: Mid-Market, Enterprise
- NIST CSF: Identify, Detect
- Pricing: Contact sales

#### Our take

CyCognito Platform discovers your external assets with black-box reconnaissance, attributes each one to an owner and business unit, and fingerprints the technology behind it. It then tests them with a large library of testing modules, validates exposures automatically and maps attack chains across assets. It also catches risks that have no CVE, such as weak configurations.

It connects to Microsoft Sentinel, Splunk, ServiceNow, Jira, CrowdStrike, Wiz, Tenable and Qualys.

It earns a place because discovery and active testing come in one product, so findings arrive already checked and not as a raw asset list. That suits mid-market and enterprise teams that want proof before they assign work. Testing live assets needs their owners on board, so settle scan cadence and scope before you turn it on.

#### CyCognito EASM Platform main features

- Zero-input external asset discovery
- Shadow IT and shadow AI discovery
- Graph-based organizational attribution of assets
- Continuous active validation of exploitability
- Risk prioritization using validated findings, business context, and threat intelligence
- Attack path visibility on specific assets
- Continuous monitoring for environment changes

#### What customers say

CyCognito looks at your company from the outside, the way an attacker would, so it turns up internet-facing assets that nobody had on the list. Customers find it quick to start and easy to learn, and it ranks risks by how exploitable they are, which lets the team work on the worst ones first. The catch is support, because when a finding turns out to be a false alarm, replies can take a long time.

#### Before you buy

Where it is strong:

- Automated validation of exposures, not only discovery
- Owner and business unit attribution for each asset
- Detects risks that have no CVE

Ask in the demo:

- Ask how fast support handles disputed findings
- Review sample fix steps to see if they are detailed enough for your team
- Confirm testing scope and timing with your app owners first

### 6. Bitsight External Attack Surface Management

**[Bitsight](https://mandos.io/data/companies/bitsight?utm_source=cybersectools.com&utm_medium=shortlist-md&utm_campaign=explore-in-mandos)**. Discovers assets, analyzes risks, and prioritizes vulnerabilities across orgs.

Boston, United States · Founded 2011 · $149M raised · Momentum 35/100 (Mandos)

Certifications: SOC 2, CSA STAR

**Best for:** Teams reporting cyber risk to boards and insurers

Product page: https://cybersectools.com/tools/bitsight-external-attack-surface-management

#### At a glance

- Vendor: Bitsight
- Headquarters: Boston, United States
- Founded: 2011
- Deployment: Cloud
- Company size: SMB, Mid-Market, Enterprise
- NIST CSF: Govern, Identify
- Pricing: Contact sales

#### Our take

Bitsight External Attack Surface Management discovers your assets and shadow IT and attributes them to the right entity with Bitsight IQ. It ranks vulnerabilities by real-world impact and monitors both your own assets and your vendors'. It syncs public IP addresses from AWS, Azure and Google Cloud, and produces executive reports and security benchmarks.

It earns a place because Bitsight IQ ties each discovered asset to the entity that owns it, and cloud IP addresses sync from AWS, Azure and Google Cloud several times a day. That suits a company with many subsidiaries or suppliers to map. Ask how attribution gets checked, since an asset tied to the wrong entity sends work to the wrong owner.

#### Bitsight External Attack Surface Management main features

- Automated asset discovery and mapping
- AI-enabled entity attribution using Graph of Internet Assets
- Shadow IT detection
- Vulnerability identification across extended attack surface
- Risk-based vulnerability prioritization
- Continuous monitoring of organizational and vendor assets
- Multi-cloud integration with AWS, Azure, and GCP
- Executive-level reporting with business outcome metrics

#### Bitsight External Attack Surface Management main integrations

AWS, Azure, GCP

#### What customers say

Bitsight's score gets read well beyond the security team, so customers use it in board reports and to show clients and peers where they stand, then raise it by fixing what it finds on their own internet-facing assets. Reviewers value the constant watch on what they expose to the internet, which helps them spot and fix weak points early, and teams often use the same view to keep an eye on their vendors. The catch is that some findings turn out to be false, so someone has to check each one before acting on it.

#### Before you buy

Where it is strong:

- Executive reports and benchmarks for boards
- Monitors your own assets and your vendors' assets
- Syncs public IPs from AWS, Azure and Google Cloud

Ask in the demo:

- Ask how disputed findings are removed from your rating and how fast
- Check whether parked or unused domains count against your score
- Confirm whether you need the vendor risk features or only your own assets

### 7. Searchlight Exposure

**[Searchlight Cyber](https://mandos.io/data/companies/searchlight-cyber?utm_source=cybersectools.com&utm_medium=shortlist-md&utm_campaign=explore-in-mandos)**. ASM platform that scans external attack surfaces hourly for vulnerabilities

Portsmouth, United Kingdom · Founded 2017 · Momentum 46/100 (Mandos)

Certifications: SOC 2, ISO 27001, Cyber Essentials

**Best for:** Teams wanting hourly scans and zero-day warnings

Product page: https://cybersectools.com/tools/assetnote-attack-surface-management-tool

#### At a glance

- Vendor: Searchlight Cyber
- Headquarters: Portsmouth, United Kingdom
- Founded: 2017
- Deployment: Cloud
- Company size: SMB, Mid-Market, Enterprise
- NIST CSF: Identify, Detect
- Pricing: Contact sales

#### Our take

Searchlight Exposure scans your external assets every hour, not once a day, so new exposures show up quickly. It discovers assets and subdomains from seed domains, verifies software versions and flags exploitable vulnerabilities and cloud misconfigurations. A research team looks for new vulnerabilities and gives early warning on zero-days, and findings come with proof-of-concept exploits.

It also spots short-lived assets and third-party services, monitors changes across your attack surface and connects to Splunk and Jira.

It earns a place on speed, because hourly scans and its own vulnerability research mean you hear about a new exposure or zero-day sooner. That suits a team whose external footprint changes every day. Ask how its proof-of-concept exploits are shared and used, because they are strong evidence but need careful handling.

#### Searchlight Exposure main features

- Hourly automated scanning of external assets
- Asset and subdomain discovery from seed domains
- Automated asset enrichment with version verification
- Detection of vulnerabilities and cloud misconfigurations
- Zero-day vulnerability research and early notification
- Proof-of-concept exploits for findings
- Shadow IT and third-party tool detection
- Ephemeral asset identification

#### Searchlight Exposure main integrations

Splunk, Jira

#### Before you buy

Where it is strong:

- Hourly scanning of external assets
- Early warning on zero-days from its own research team
- Proof-of-concept exploits attached to findings

Ask in the demo:

- Ask for customer references, since public reviews are thin
- Confirm which systems findings can be sent to
- Check how version verification cuts false alarms on your assets

## How they fit your cybersecurity program (NIST CSF)

NIST CSF 2.0 has six functions: Govern, Identify, Protect, Detect, Respond and Recover. The grid shows which functions each pick maps to in our record, so you can see where a solution sits in your program and what it leaves to other controls.

All 7 solutions map to Identify. 1 of 7 maps to Govern. 1 of 7 maps to Protect. 6 of 7 map to Detect. None map to Respond or Recover.

| Solution | Govern | Identify | Protect | Detect | Respond | Recover |
| --- | --- | --- | --- | --- | --- | --- |
| All solutions on this list | 1 of 7 | 7 of 7 | 1 of 7 | 6 of 7 | 0 of 7 | 0 of 7 |
| Palo Alto Networks Cortex Xpanse | – | 2 of 3 (Asset Management, Risk Assessment) | 1 of 5 (Technology Infrastructure Resilience) | 1 of 2 (Continuous Monitoring) | – | – |
| Microsoft Defender EASM | – | 2 of 3 (Asset Management, Risk Assessment) | – | 1 of 2 (Continuous Monitoring) | – | – |
| Mandiant Attack Surface Management | – | 1 of 3 (Asset Management) | – | 1 of 2 (Continuous Monitoring) | – | – |
| Censys Attack Surface Management | – | 2 of 3 (Asset Management, Risk Assessment) | – | 2 of 2 (Continuous Monitoring, Adverse Event Analysis) | – | – |
| CyCognito EASM Platform | – | 2 of 3 (Asset Management, Risk Assessment) | – | 1 of 2 (Continuous Monitoring) | – | – |
| Bitsight External Attack Surface Management | 1 of 6 (Cybersecurity Supply Chain Risk Management) | 2 of 3 (Asset Management, Risk Assessment) | – | – | – | – |
| Searchlight Exposure | – | 2 of 3 (Asset Management, Risk Assessment) | – | 1 of 2 (Continuous Monitoring) | – | – |

Each cell shows how many of the function's NIST CSF 2.0 categories the solution maps to, with the category names.

A product helps you reach these outcomes, but it does not make you compliant on its own. Your people and processes do the rest.

## CISO checklist for selecting an External Attack Surface Management product

Work through these steps in order to go from an unknown attack surface to a contract you can defend.

1. **Gather your known domains, IP ranges and cloud accounts.** These seeds decide how much the product can discover in a trial.
2. **Run a discovery trial and compare it with your asset list.** The number of assets you did not know about is the clearest test of value.
3. **Check how each asset is tied to an owner.** Findings without an owner rarely get fixed.
4. **Review how false positives are handled and removed.** Customers in this category often complain about false alarms that take time to clear.
5. **Decide whether you need active testing or discovery only.** Testing proves exposures but needs scope agreements and costs more.
6. **Confirm links to your ticketing, SIEM and scanners.** Exposures need to reach the teams that fix them.
7. **Ask how fast new assets and zero-day exposures appear.** Attackers move within hours of a new flaw going public.
8. **Check coverage of subsidiaries and acquired companies.** Inherited assets are a common blind spot.
9. **Get pricing based on your real asset count.** Pricing often grows with assets, and your count will rise after discovery.

**Compare External Attack Surface Management solutions side by side**

Features, integrations, NIST coverage and deployment for every External Attack Surface Management solution we list, in one table.

[Compare External Attack Surface Management solutions →](https://cybersectools.com/compare)

## Other solutions we considered for this shortlist

We looked at 91 products for this list. These did not make the 7 above but are worth a look for the right team.

1. [NetSPI External Attack Surface Management (EASM)](https://cybersectools.com/tools/netspi-external-attack-surface-management-easm) · NetSPI
   Continuous discovery, monitoring, and testing of external assets and exposures
2. [Cytrusst: Attack Surface Management (ASM)](https://cybersectools.com/tools/cytrusst-cyber-attack-surface-management) · Cytrusst
   Cytrusst ASM is an attack surface management product that helps discover an organization's
3. [Hadrian Agentic AI](https://cybersectools.com/tools/hadrian-agentic-ai) · Hadrian
   AI-powered platform for continuous attack surface discovery and pentesting
4. [ImmuniWeb® Discovery](https://cybersectools.com/tools/immuniweb-discovery) · ImmuniWeb
   ImmuniWeb Discovery is an attack surface management platform that continuously monitors an organization's external digital assets for security vulnerabilities, misconfigurations, and threats across domains, applications, cloud resources, and the dark web.
5. [Attaxion](https://cybersectools.com/tools/attaxion)
   Agentless EASM platform for asset discovery, exposure mgmt & risk reduction.
6. [Siemba EASM](https://cybersectools.com/tools/siemba-easm) · Siemba
   AI-driven EASM platform for discovering and monitoring external-facing assets
7. [DarknetSearch Attack Surface Discovery](https://cybersectools.com/tools/darknetsearch-attack-surface-discovery) · Kaduu
   Attack surface discovery platform monitoring digital assets and data exposures
8. [GuardEon](https://cybersectools.com/tools/guardeon) · Infilux AppSec
   Agentless external attack surface & dark web monitoring platform.
9. [TRaViS](https://cybersectools.com/tools/travis) · TRaViS ASM
   AI-enhanced EASM platform for external attack surface discovery and monitoring.

Explore all External Attack Surface Management solutions: https://cybersectools.com/categories/external-asm

## Conclusion

Start with how much you already know about your internet presence. If your asset list is thin, a discovery-first product gives the quickest win. Cortex Xpanse leads for large estates and adds automated fixes, and Microsoft Defender EASM is the natural fit if you run on Microsoft. If you want proof that exposures are real, CyCognito adds active testing.

Bitsight suits teams that report a security score to boards and insurers. Censys, Mandiant and Searchlight bring strong internet data and research, but have fewer public reviews, so ask for references.

## Frequently Asked Questions

### What is the difference between EASM and a vulnerability scanner?

A vulnerability scanner checks the assets you tell it about. EASM finds assets you did not know you had, then watches them. Many teams use EASM to feed new assets into their scanner.

### What is shadow IT in this context?

Shadow IT means systems set up outside the security team's view, such as a cloud server a developer launched or a marketing site on a new domain. EASM finds them by looking at your company from the outside.

### Is active testing safe for production systems?

Products that test actively use payloads meant to be harmless, but you should still agree on scope and timing with app owners. Start with a small set of assets and widen it once you trust the results.

### How does EASM help with acquisitions?

Before or after a deal, EASM maps what the acquired company exposes online. That shows inherited risk, such as old servers or forgotten domains, before you connect their network to yours.

### How often should external assets be scanned?

Daily is common, and some products scan hourly. Faster scans matter when new zero-days are being exploited quickly. Ask how fast new assets appear in the inventory, not only how often scans run.

## Sources

These are the pages we reviewed for each pick: the vendor's own product page and website, its market data on Mandos, and every review page we read for customer feedback.

1. **Palo Alto Networks Cortex Xpanse** · Palo Alto Networks: [Product page](https://www.paloaltonetworks.com/cortex/cortex-xpanse/) · [Palo Alto Networks website](https://www.paloaltonetworks.com/) · [Market data on Mandos](https://mandos.io/data/companies/palo-alto-networks?utm_source=cybersectools.com&utm_medium=shortlist-md-sources&utm_campaign=explore-in-mandos) · [Gartner Peer Insights: cortex xpanse](https://www.gartner.com/reviews/product/cortex-xpanse) · [PeerSpot](https://www.peerspot.com/products/cortex-xpanse-reviews) · [Gartner Peer Insights: cortex xpanse expander](https://www.gartner.com/reviews/product/cortex-xpanse-expander)
2. **Microsoft Defender EASM** · Microsoft: [Product page](https://www.microsoft.com/en-us/security/business/cloud-security/microsoft-defender-external-attack-surface-management/) · [Microsoft website](https://www.microsoft.com/) · [Market data on Mandos](https://mandos.io/data/companies/microsoft?utm_source=cybersectools.com&utm_medium=shortlist-md-sources&utm_campaign=explore-in-mandos) · [Gartner Peer Insights](https://www.gartner.com/reviews/product/microsoft-defender-external-attack-surface-management) · [Reddit: defender easm roadmap](https://www.reddit.com/r/DefenderATP/comments/1sskz74/defender_easm_roadmap/) · [Reddit: best tools for external attack surface management](https://www.reddit.com/r/sysadmin/comments/1phscyb/best_tools_for_external_attack_surface_management/) · [G2](https://www.g2.com/products/microsoft-defender-external-attack-surface-management/reviews) · [Reddit: integration of microsoft defender easm with](https://www.reddit.com/r/DefenderATP/comments/1eklkj1/integration_of_microsoft_defender_easm_with/) · [Reddit: defender external attack surface management](https://www.reddit.com/r/AZURE/comments/wfizq6/defender_external_attack_surface_management/)
3. **Mandiant Attack Surface Management** · Google: [Product page](https://cloud.google.com/security/products/attack-surface-management/) · [Google website](https://www.google.com/) · [Market data on Mandos](https://mandos.io/data/companies/google?utm_source=cybersectools.com&utm_medium=shortlist-md-sources&utm_campaign=explore-in-mandos) · [Gartner Peer Insights](https://www.gartner.com/reviews/product/mandiant-advantage-attack-surface-management-legacy)
4. **Censys Attack Surface Management** · Censys: [Product page](https://censys.com/product/attack-surface-management) · [Censys website](https://censys.com/) · [Market data on Mandos](https://mandos.io/data/companies/censys?utm_source=cybersectools.com&utm_medium=shortlist-md-sources&utm_campaign=explore-in-mandos) · [Gartner Peer Insights](https://www.gartner.com/reviews/product/censys-attack-surface-management) · [Reddit: how do you do external attack surface monitoring](https://www.reddit.com/r/cybersecurity/comments/1ekqesj/how_do_you_do_external_attack_surface_monitoring/) · [Reddit: what easm tools are actually working for lean](https://www.reddit.com/r/cybersecurity/comments/1s4ka4d/what_easm_tools_are_actually_working_for_lean/)
5. **CyCognito EASM Platform** · CyCognito: [Product page](https://www.cycognito.com/platform/attack-surface-management.php) · [CyCognito website](https://www.cycognito.com/) · [Market data on Mandos](https://mandos.io/data/companies/cycognito?utm_source=cybersectools.com&utm_medium=shortlist-md-sources&utm_campaign=explore-in-mandos) · [G2](https://www.g2.com/products/cycognito/reviews) · [Gartner Peer Insights](https://www.gartner.com/reviews/product/cycognito-platform) · [PeerSpot](https://www.peerspot.com/products/cycognito-reviews)
6. **Bitsight External Attack Surface Management** · Bitsight: [Product page](https://bitsight.com/products/external-attack-surface-management/) · [Bitsight website](https://www.bitsight.com/) · [Market data on Mandos](https://mandos.io/data/companies/bitsight?utm_source=cybersectools.com&utm_medium=shortlist-md-sources&utm_campaign=explore-in-mandos) · [PeerSpot](https://www.peerspot.com/products/bitsight-reviews) · [Gartner Peer Insights](https://www.gartner.com/reviews/product/bitsight-cyber-risk-intelligence) · [Reddit](https://www.reddit.com/r/cybersecurity/comments/1s4ka4d/what_easm_tools_are_actually_working_for_lean/)
7. **Searchlight Exposure** · Searchlight Cyber: [Product page](https://www.slcyber.io/exposure) · [Searchlight Cyber website](https://slcyber.io/) · [Market data on Mandos](https://mandos.io/data/companies/searchlight-cyber?utm_source=cybersectools.com&utm_medium=shortlist-md-sources&utm_campaign=explore-in-mandos) · [Reddit: best threat intelligence attack surface](https://www.reddit.com/r/msp/comments/1jqede2/best_threat_intelligence_attack_surface/) · [Reddit: what easm tools are actually working for lean](https://www.reddit.com/r/cybersecurity/comments/1s4ka4d/what_easm_tools_are_actually_working_for_lean/)

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For AI agents: every CybersecTools shortlist is listed at https://cybersectools.com/shortlists.md.

More on the vendors on this list: funding, momentum, hiring and news, plus the full product and company record, are available through the Mandos MCP Server (paid plans), which connects to AI assistants: https://mandos.io/mcp?utm_source=cybersectools.com&utm_medium=shortlist-md