Compare 10+ External Attack Surface Management (EASM) Tools

Several attack surface management (ASM) and external attack surface management (EASM) tools have emerged recently. In this article, I picked the best 10+ platforms based on their asset discovery level and attack surface management capabilities. Here are my key takeaways:

Asset discovery level

See the explanation for asset discovery methods.

Asset discovery levels:

• Manual – Scans only manually provided assets; no automatic discovery.
• Scripted – Uses public data (DNS, WHOIS, certs) or basic cloud integrations to find assets.
• Semi-automated – Combines scans, threat intel, and cloud data with some manual oversight.
• Highly autonomous – AI/ML-based continuous discovery with little to no human input.

Attack surface management capabilities

• Brand monitoring – Detects brand impersonation and phishing attempts across domains and digital platforms.
  
• Website Scanning – Identifies vulnerabilities and misconfigurations in public-facing websites and web applications.
  
• API Scanning – Detects exposed or vulnerable APIs and monitors for unauthorized access or misused endpoints.

External vs. internal attack surface

Source: UpGuard¹  

• ASM (Attack Surface Management) – Focuses on internal and external assets (servers, endpoints, databases, applications, cloud resources). It is carried out exclusively from the hacker’s viewpoint. 

• EASM (External Attack Surface Management) – Focuses only on external assets exposed to the internet (domains, IPs, ports, certificates, public APIs, exposed cloud assets). It is carried out exclusively from the hacker’s viewpoint. 

Below is a comparison of ASM/EASM types:

Withrotate

WithRotate is a cloud-based cybersecurity platform designed for small and mid-sized businesses (SMBs, SMEs) and managed service providers (MSPs). Apart from EASm, it offers five integrated modules: Identity, Email, Endpoint, Training, and Monitoring.

Key features:

Continuous monitoring and visibility:

• Continuously scans the internet to detect public-facing assets, including domains, IP addresses, ports, and certificates.
  
• The EASM Hub performs ongoing internet-wide scanning of domains, IP addresses, ports, SSL certificates, etc., building a dynamic asset list.

Real-time vulnerability detection and prioritization:

• Identifies vulnerabilities (e.g., expired SSL certificates, open ports) in real time across your external attack surface.
  
• Highlights high-risk and likely-to-be-targeted assets.

Remediation support with Rotate AI:

• Provides AI-powered analysis to explain and contextualize discovered vulnerabilities. (e.g., flagging a misconfigured S3 bucket as publicly accessible and identifying sensitive filenames like user_data.csv).
  
• Delivers step-by-step remediation guidance.

Centralized dashboard for risk management:

• Consolidates all findings in a single interface for unified visibility.
  
• Enables prioritization of critical issues and streamlines response efforts across teams.

Pros✅

• Designed for SMBs and MSPs: Suitable for organizations with small or no dedicated security teams. Offers out-of-the-box functionality requiring minimal setup.
• Unified platform: Offers attack surface management, remediation workflows, security awareness training, and phishing simulations in a single dashboard.
• Built-in security training: Includes phishing simulation training modules.
  

Cons❌

• No Windows endpoint agent: Endpoint protection features are available only for macOS environments.
• Limited third-party integrations: Fewer integrations than some enterprise-grade competitors.

Microsoft Defender External Attack Surface Management

Microsoft Defender External Attack Surface Management (EASM) is effective for discovering and managing internet-facing assets, utilizing known “seeds” such as domains and IP addresses to uncover related infrastructure. Integrates seamlessly with Microsoft Sentinel.

A 30-day free trial is available.

Key features:

• Discovery and inventory: Identifies known and unknown assets related to the organization, including domains, IP blocks, hosts, and email contact records. Assets are indexed, categorized, and continuously updated.
• Risk insight dashboards: Show critical risks such as vulnerabilities and compliance gaps.
• Asset management with custom filtering: Enables users to filter and customize asset inventories, such as newly discovered cloud services.
• Role-based access control: Supports fine-grained permissions
• Data residency and compliance: Stores customer data in selected regions. Data is deleted 180 days after service termination.

Pros✅

• Scalability: Organizations with large external environments, such as enterprises or public institutions, can accumulate a high number of assets.
• Discovery engine: Uses known domains, IP blocks, and WHOIS data to recursively map all connected assets, providing deep visibility into external infrastructure.
  
• Automated and dynamic inventory: Supports prebuilt and custom inventories, with continuous discovery and classification of assets (e.g., approved, candidate, monitor-only).
  
• Azure-native deployment: Easily set up and manage via the Azure portal with integration into broader Microsoft Defender tools.
  

Cons❌

• Complex setup and integration: Initial deployment can be challenging for organizations with diverse IT environments or limited Azure experience.
• Performance limitations: Can be slow during peak usage; resource-intensive.
• Pricing impact on SMBs: While usage-based pricing is transparent, costs can scale quickly with asset count, making it less accessible for small organizations.

Panorays

Panorays is a third-party security risk management platform that combines external attack surface visibility with automated vendor risk assessment workflows. It’s designed to help organizations evaluate, monitor, and manage the cybersecurity posture of their suppliers and partners.

It’s best for companies that combine technical scanning with governance workflows in a single platform, making it especially useful for mid-sized or enterprise teams building mature vendor risk management programs.

Key features:

• Automated security questionnaires: Enables companies to send customized security questionnaires to vendors. Automates response tracking, scoring, and follow-up, reducing manual effort.
• Risk scoring: Combines external scan results and questionnaire responses to generate a unified, contextualized risk score per vendor.
• Remediation workflows: Suggest remediation workflows for risk teams to collaborate with vendors directly within the platform, addressing identified gaps.

Pros✅

• Strong third-party risk management capabilities: Enables automated security questionnaires, continuous vendor monitoring, and structured risk scoring.
• User-friendly interface: Widely praised for being intuitive and accessible, even for non-technical stakeholders.
• Customization and integration: Customizable questionnaires and risk profiles; integrates with tools like Power BI and (to some extent) Jira.

Cons❌

• Scalability issues: Enterprises with thousands of vendors report occasional platform slowdowns during bulk actions.

• False positives: Alerts, such as “compromised credentials,” are sometimes triggered by deactivated accounts.
  
• Limited financial risk context: Does not currently quantify the potential financial impact of vendor breaches.

Halo Security

Halo Security is an external attack surface management platform that offers asset discovery, risk and vulnerability assessment, and manual penetration testing services through a unified dashboard.

Focuses on external visibility: Scans public-facing assets like:

• Third-party scripts: Monitor JavaScript activity across websites.
• TLS certificates: Spot expired, mismatched, or weak encryption certificates.
• HTTP headers: Check for missing or misconfigured security headers (e.g., Content Security Policy, or CSP).
• Missing patches: Find unpatched software with known vulnerabilities.
• OWASP threats: Detect common web app risks like SQL injection.

Key features:

• Attack surface inventory: Keeps a current list of all internet-facing assets.
• External vulnerability management: Monitors and remediates risks on public assets.
• Subsidiary risk monitoring: Tracks the external security of affiliates and subsidiaries.

Pros✅

• Ease of use: Lightweight tool for non-technical teams.
• PCI compliance support: Granular scanning and automated reporting for PCI compliance.
• Customizable risk insights: Offers detailed security insights tailored to an organization’s specific needs and threat posture.

Cons❌

• Integration flexibility: Requires effort to connect with some existing systems
• Access configuration: User role setup and permissions could be more streamlined.

Crowdstrike Falcon Surface 

CrowdStrike EASM provides a unified platform that consolidates external attack surface management (EASM), risk-based vulnerability management (RBVM), cyber asset attack surface management (CAASM) and IT asset management (ITAM) tools.

The module’s automatic risk prioritization is based on: 

• Business context: geolocation, industry, cyberattack history 
• Asset type 
• CVE scores 
• Manual edits

Key features:

• Full attack flow visibility (XDR): When integrated with Identity Protection, CrowdStrike can trace incidents back to the source (e.g., a compromised IT admin).
• Real-time threat detection: Provides immediate threat identification and response.
• Risk prioritization: You can navigate through Falcon Surface by CrowdStrike vulnerability management dashboard to prioritize risks.
• Compliance and forensic reporting

Source: CrowdStrike²

• Real-time Internet mapping: Users can map known and unknown assets, identify exposures, and monitor cross-environment security concerns for a centralized security overview.

Source: CrowdStrike³

Pros✅

• Clear action visibility in SIEM integration: Unlike other tools, CrowdStrike provides action logs, enabling users to verify the actions taken during incidents.
• Deep investigation capabilities: Users can access logs, file history, network connections, and malicious processes, as well as other relevant data, going back several days, to perform thorough forensic investigations.
• Real-time detection and response (RTR): CrowdStrike enables real-time enforcement of security policies (e.g., USB control), triggering responses without delay.
• IOC ingestion and proactive threat response: The platform supports ingesting indicators of compromise (IOCs) and using them for future threat detection and automated investigations.
• Remote investigation capabilities: Allows security teams to access other devices during incident investigations.
  

Cons❌

• No automated IOC integration: Indicator of compromise (IOC) ingestion from external vendors is manual.
• Complex query language: The built-in query system is difficult to learn. 
• Limited user-friendly search tools: Search tabs and query input methods could be simplified.
• Challenging cloud deployment: Setting up a cloud environment is not seamless and can be difficult for some teams to implement.

Scrut Automation

Scrut Automation is a governance, risk, and compliance (GRC) platform with extended capabilities in cloud security monitoring and internal risk visibility.

While it’s not a full-fledged EASM tool, Scrut provides compliance automation alongside asset visibility within connected cloud environments. For example, it integrates with AWS, Azure, and GCP to continuously monitor configurations, access controls, and deployed resources.

Key features:

• Compliance-focused solution. Scrut is purpose-built for organizations aiming to automate frameworks like SOC 2, ISO 27001, HIPAA, and GDPR.
• Cloud asset visibility. Scrut provides continuous visibility into cloud infrastructure (e.g., AWS, Azure, GCP), SaaS apps, code repositories, and IAM policies.
• Unified GRC dashboard. Risk assessments, policy controls, access reviews, vendor risk, and security training are all managed from a single platform.
• Broad integrations. Supports 70+ prebuilt integrations with tools like Google Workspace, AWS, Azure, Okta, and Jira.

Pros✅

• Built-in tools for managing vendors, employees, access reviews, and security awareness.
  
• Responsive customer support and audit-readiness assistance.
  
• Strong fit for startups in regulated industries.

Cons❌

• Not a full-fledged EASM platform. Scrut does not scan the internet for unknown or externally exposed assets (e.g., shadow IT, rogue domains).
  
• No brand or web exposure monitoring. Lacks features like phishing detection, domain spoofing alerts, or external API scanning.
  
• Focused on known environments. Discovery is limited to assets Scrut is directly connected to (e.g., via cloud integrations or manual input).

WIZ

The Wiz users can identify and display possible resource exposure. Wiz scans all levels of the cloud and Kubernetes to create a network topology.

Key features:

• Dynamic scanner can assist you in prioritizing risks and providing you with an attacker’s perspective on your surroundings.
  
  It will attempt to connect from the outside to resources to assess possible exposure and discover IP addresses and ports, exactly as a hacker would. 

Source: Wiz⁴  

• Automated risk alerts send alerts/notifications when significant changes in a vendor’s external footprint or risk profile are detected.

Pros✅

• Cloud configuration gap detection & vulnerability management: Customers say that Wiz offers significant benefits, particularly for cloud configuration gap detection, vulnerability management, and compliance monitoring.
• Inventory management & AWS CIS framework: Users appreciate Wiz’s ability to provide consolidated results for cloud assets, including an overview of inventory management and alignment with frameworks like AWS CIS.

Cons❌

• Reporting options: More customization and flexibility in the reporting can be added.
• Consolidation of alerts: The platform could improve by consolidating similar alerts instead of categorizing them based on varying severity levels.
• No real-time malware scanning

SentinelOne Singularity Cloud

SentinelOne Singularity Cloud is an attack surface management (ASM) solution that combines Cloud security posture management (CSPM), cloud workload protection platforms (CWPP), and data security posture management DSPM for real-time cloud security.

SentinelOne Singularity Cloud provides 4 types of attack surface management:

1. Application attack surface management: Detecting weaknesses in software applications (e.g., web apps, mobile apps) that could expose sensitive data or user accounts.
2. Network attack surface management: Identifying vulnerabilities in network infrastructure (e.g., routers, switches, firewalls) that attackers can exploit for unauthorized access.
3. Device attack surface management: Security risks in physical devices (e.g., laptops, smartphones) that can be targeted to steal data or launch further attacks.
   
   
   
4. Identity attack surface management: Enables cloud administrators to control who may access what and under what conditions. 

User can manage the security of their data residing in the cloud with:  

• User authentication and access
• Roles & least privilege

Source: SentinelOne⁵

Pros✅

• Transparent read-only access: Transparent read-only access that ensures no actions are taken without their explicit approval.
• Integration with JIRA: Seamless integration with JIRA.
• Asset management: Centralized view across cloud environments.

Cons❌

• False positives: Higher rate of false positives compared to other platforms.
• Scalability: Limited performance and automation in large-scale environments.
• Technical: Insufficient guidance for teams without deep cloud expertise and non-developers.

CyCognito Attack Surface Management

CyCognito is an enterprise-grade EASM platform designed to provide deep, attacker-like visibility into an organization’s external attack surface.

Best for organizations focused on external threat prevention, shadow IT discovery, and third-party exposure.

Key features:

• Zero-input discovery: Automatically maps an organization’s business structure and associated digital assets using only the company name—no manual input or asset lists required.
• Automated asset classification: Identifies ownership and business context (e.g., which department, region, or brand) for each asset.

Pros✅

• Comprehensive external asset discovery: Effectively identifies internet-facing assets, including unknown or unmanaged systems.
  
• Risk-based prioritization: Uses contextual analysis to score vulnerabilities based on likelihood and impact.
  

Cons❌

• False positives reported: Alerts required manual investigation.

UpGuard

UpGuard is a cybersecurity platform focused on third-party risk management and external attack surface monitoring.

Best for:

• Teams that need to monitor vendors’ external exposure (e.g., misconfigured domains, leaked credentials, open ports).
• Organizations without complex governance, risk, compliance (GRC) stacks but requiring a lightweight platform for security due diligence.

Key features:

• Automated asset discovery: UpGuard’s automated asset discovery approach connects domains and IP addresses to your company using active and passive DNS, and other fingerprinting techniques.

Source: UpGuard⁶

• Third-party cyber risk detection: UpGuard’s risk profile function detects poorly maintained web pages, out-of-date web server software, and vulnerabilities in Microsoft Exchange server software.

Source: UpGuard⁷  

Pros✅

• Vulnerability detection: Effectively scans external surfaces, including vendor domains and third-party risks.
• Customization: Supports tailored controls for standards like ISO27001:2022 and DPDPA.

Cons❌

• SaaS and behavior gaps: Does not monitor SaaS apps or user behavior risks.
  
• Performance and support: Occasional lags and slow support response times.

Mandiant Advantage Attack Surface Management by Google

While Mandiant Advantage ASM is not a standalone EASM platform, it enhances threat-focused prioritization within Google-centric environments by integrating asset discovery with contextual threat intelligence. 

For example, it uses signals, such as known exploits, to prioritize exposed assets discovered across Google Cloud, hybrid, and third-party environments.

Its automated discovery,  prioritization, and integration-ready workflows make it a good fit for teams that need risk insight tied closely to threat context. 

Key features:

• Incident response: Assets are linked with threat detection insights, enabling mapping of incidents.
• Prioritization engine: Considers exploitability, CVE status, and business impact to rank issues.

Pros✅

• Automated discovery: Identifies cloud, on-prem, and third-party assets without manual input.
• Response workflows: Supports remediation through API access and integration with SIEM/SOAR tools.
  
• Google Cloud integration: Natively connects with Google’s security tools.

Cons❌

• Focused on Google ecosystem: The Best experience and integration are for organizations aligned with Google Cloud.
  
• Limited standalone EASM depth: Compared to pure-play EASM platforms, less focus on brand monitoring or deep attacker simulation.
  
• Pricing and licensing complexity: Pricing details are not readily available; integrated licensing may require broader platform commitments.

Tenable Attack Surface Management

Tenable is a well-established vulnerability management platform known for its deep scanning capabilities, asset discovery, and compliance reporting across on-prem, cloud, and hybrid environments.

The platform performs adequately when stable, but deeper technical issues are difficult to resolve. Documentation lacks clarity. Even with a paid support plan, the quality of assistance does not consistently meet expectations.

Key features: 

• Asset inventory management: You can view your external-facing asset inventory from previously added data or you can add further hosts, domain names.

• Click Manage Columns in the top-right menu to view all available data fields.

• You can filter or query different data types. For example, if you need to find any assets that have port 443 open, you can use the search filter to bring up assets available with 443 in your inventory.

Source: Tenable Nessus⁸

Pros✅

• External infrastructure mapping: Efficiently maps clients’ public-facing assets and continuously updates changes.
• Business context dashboards Display scan results within the business context, making management reporting easier for both technical and non-technical teams.

Cons❌

• Support challenges: Multiple users cited slow response times, poor coordination, or unhelpful interactions.
• Ease of deployment: IT consultants note that the initial deployment is difficult.

Intruder

Intruder is primarily a vulnerability scanner and management platform. It lacks key EASM capabilities such as automated asset discovery. Its easy UI reporting capabilities could be useful for teams that don’t have a dedicated security department.

Key features:

• Manual asset-based scanning: No automatic discovery of unknown or shadow assets, which limits its ability to map the entire external attack surface.
• Vulnerability assessment: Performs continuous vulnerability scans on defined targets.
• Threat scanning: Detects newly disclosed threats through built-in emerging threat scans (not available in the starting plan)

Pros✅

• Automated vulnerability scanning: Supports scheduled vulnerability scans.
• Compliance reporting: Supports security needs for standards like PCI and ISO 27001, including reporting and vulnerability scans.

Cons❌

• No automated asset discovery: Does not automatically identify or map unknown assets. It only scans assets that are manually provided. 
• Scan flexibility: Users noted that scans can be slow and can’t be filtered to focus on specific vulnerabilities.
• No threat intelligence enrichment

Conclusion

Choosing the right external attack surface management (EASM) platform depends on your infrastructure size, cloud footprint, integration needs, and budget. While most tools offer similar features, their effectiveness in asset discovery, risk prioritization, and scalability varies widely.

For example, CyCognito is a strong choice for enterprises needing automated discovery across subsidiaries and supply chains, while Halo Security suits mid-market organizations seeking vulnerability scanning and compliance support without AI-driven internet-wide scanning.

Explanation for asset discovery methods

• Subdomain scanning: Identifies subdomains linked to known domains using DNS and certificate transparency.
  
• Manual input: Scans only assets manually provided by the user.
  
• Cloud sync: Automatically discovers cloud assets via API integration with cloud providers.
  
• OSINT-based mapping: Uses public data (DNS, WHOIS, SSL) to identify assets linked to your organization.
  
• Cloud integration: Pulls asset inventories directly from cloud platforms like AWS, Azure, or GCP.
  
• External scanning: Actively scans internet-facing infrastructure for exposed services and vulnerabilities.
  
• Exposure scan: Evaluates discovered assets for potential security weaknesses (e.g., misconfigured services, outdated software).
• Threat Intel: Pulls data from threat intelligence feeds (e.g., dark web, malware command-and-control lists).
  
• AI-driven Internet-wide scanning: Automatically discovers unknown or untracked infrastructure without needing input.

Further reading

• Intrusion Prevention: How does it work? & 3 Methods
• Role-based access control (RBAC)  
• Network Segmentation: 6 Benefits & 8 Best Practices

External Links

• 1. What is External Attack Surface Management (EASM)? | UpGuard. UpGuard
• 2. Secure Your External Attack Surface | CrowdStrike EASM. CrowdStrike
• 3. Secure Your External Attack Surface | CrowdStrike EASM. CrowdStrike
• 4. Wiz enhances dynamic scanner to analyze and validate external exposure | Wiz Blog. Wiz.io
• 5. Singularity™ Product Tours - SentinelOne.
• 6. Top 10 Attack Surface Management Software Solutions in 2025 | UpGuard. UpGuard
• 7. Top 10 Attack Surface Management Software Solutions in 2025 | UpGuard. UpGuard
• 8. https://www.youtube.com/watch?v=DijXEs9yWF4.