Based on our experience developing both external attack surface management (EASM) and continuous threat exposure management (CTEM) solutions, the best way to compare CTEM vs EASM processes is to look at what happens after asset discovery.
CTEM goes further than EASM and validates theoretical risks through attack vector exploitation and testing to cut false positives and give a much more actionable view of attack surface risks.
That’s why EASM could be considered an introductory or partial process within a more comprehensive CTEM workflow.
External attack surface management
External attack surface management (EASM) involves finding vulnerabilities in external network assets (many of which are unmanaged) but does not validate them or coordinate remediation as CTEM does.
Continuous threat exposure management
Continuous threat exposure management (CTEM) takes a five-stage approach to managing external attack surface risk. External-facing assets are scoped and discovered (like EASM) but are also prioritized, validated, and then fixed during the final mobilization stage.
| Type | CTEM | EASM |
| Definition | The discovery, scoping, prioritization, mobilization, and validation of attack surface risks done continuously. | The discovery and prioritization of assets without validation. |
| Process Involved | Discovery, scoping, prioritization, mobilization, and validation of attack surface risks. | Discovery and prioritization of assets without the validation step. |
| Validation of Risk | Yes. Validates theoretical findings by actually testing and exploiting vulnerabilities. | No. Does not involve validation; findings remain theoretical and untested. |
| Results | Realistic. Provides proof of real risks by exploiting vulnerabilities. | Theoretical. Findings are theoretical and logged as potentially exploitable without proof. |
| False Positives | Low. Reduced due to validation. CTEM is more precise and generates less noise. | High. Higher possibility of false positives; may report issues that are not actually dangerous.¸ |
External attack surface management (EASM) vs continuous threat exposure management (CTEM)
The rest of this article further breaks down the differences between CTEM and EASM.
EASM takes a theoretical approach to risk discovery and prioritization
Cloud instances, SaaS apps, exposed credentials, etc. These known and unknown public-facing ICT assets often either directly contain valuable data or potential entry routes into your network or can be leveraged as part of a wider attack.
The EASM process identifies risks in these assets by working outwards from a central corporate URL in a mostly automated process. However, this discovery process is also likely to flag many potential false positives or false negative risks.
To help security teams make sense of the list of discovered assets, EASM solutions will sort their observations into different severity levels, e.g., low, medium, and high. These might range from self-signed certificates on internal-only dashboards to SQL injection vulnerabilities in user-facing web apps.
However, EASM tools can only use a theoretical or generic understanding of ” risk ” to give this assessment. If an asset contains a known dangerous CVE, EASM will say it is highly at risk; if it has only a low-risk vulnerability, it will say it is at low risk, etc.
→ Relying on EASM alone will create a high number of false positives and result in a poor understanding of real risk.
The problem with how EASM presents data to security teams is twofold.
- Firstly, taking a purely theoretical approach to risk will result in there being too many risks to remediate (as a result, low and medium-risk vulnerabilities are likely to be ignored by security or IT teams forever).
- Secondly, real-world cyber attacks do not happen based on version number alone, and judging risks based on version types does not reflect true security gaps.
To reduce external attack surface risk, organizations need to evolve beyond EASM and towards CTEM.
CTEM validates risks with real testing and coordinates the process of solving them
Both EASM and CTEM are continuous processes, but the CTEM process loop is much larger.
While EASM takes a broader approach to discovering assets, CTEM starts scoping based on the business value of their organization’s assets. What functions are important and business-critical?
From there, CTEM scans outward to discover the public-facing assets connected to these parts of the environment. The scanning happens in the same way as EASM and is also automated.
However, once the CTEM discovery phase returns a prioritized list of risks, those risks are tested to see if they are actually dangerous. Potential risks like misconfigured cloud instances or vulnerable web forms are tested with the same kind of attack vectors they would face from threat actors.
The results from this testing are used to sort risks based on their true severity and map out exploitation paths that need to be fixed. This process is called validation and is an essential part of the CTEM process that does not feature in EASM.
→ Validation is the process of testing the exploit potential of vulnerabilities in the setting in which they exist.
Validating risks is a key advantage of the CTEM process over EASM because vulnerabilities or misconfigurations in external assets will create very different levels of risk based on their environmental setting.
An asset with a critical vulnerability may be redundant and effectively isolated from the rest of your network. On the other hand, a less critical vulnerability could be present in a highly exposed asset that contains regulated personally identifiable information (PII).
These circumstances are entirely unique to an organization. That’s why theoretical prioritization is not good enough, and true attack surface risk reduction requires validation.
→ CTEM combines knowledge of ICT assets’ business value with real testing of risks to tell security teams exactly where to focus their remediation efforts.
Mobilization is another EASM vs CTEM difference
CTEM also brings in a dedicated process of fixing risks called “mobilization.” This is something that is not present in an EASM workflow.
During the early part of any CTEM workflow, the decision to prioritize certain assets is made based on the business risk they create. The responsibility for solving any risks discovered is assigned to the owners of those assets.
→ CTEM mobilizes stakeholders to fix risks.
CTEM mobilization teams are able to use the continuous data created by asset discovery, prioritization, and validation to target their priorities and track the impact of their solutions.
Because CTEM is continuous, a mobilization team can see whether they have reduced their organization’s external-facing risk and, if not, where to redirect their work.
Deploy Rapid CTEM Benefits In Your Environment
According to Gartner, organizations that practice CTEM will experience 3x less breaches than those that don’t.
The most rapid and effective way to get CTEM benefits is to use a CTEM platform like Element Security.
Within minutes of deployment, Element Security can automatically discover and validate your attack surface risks across all external assets.
We provide full-cycle CTEM capability in a single solution.
Try a free demo to see how easy it is to get CTEM benefits in your environment.
CTEM vs EASM FAQs
Is an EASM solution required for CTEM?
While you can use an EASM solution to do some of the CTEM processes, it’s much more effective to use a full-cycle CTEM platform that combines external attack surface discovery with the rest of the CTEM stages.
Is CTEM better than EASM?
In our opinion, the short answer is yes.
CTEM is a more evolved and comprehensive process for managing external attack surface risks than EASM.
The core benefits of CTEM are fewer false positives, more detailed assessment of risks, and faster remediation.
Can CTEM and EASM be used together?
Yes, EASM can be used within the CTEM process. EASM can handle the discovery of assets while CTEM goes further.