# Cobalt Attack Surface Monitoring vs S3BucketList: side-by-side comparison (2026)

[Cobalt Attack Surface Monitoring](https://cybersectools.com/tools/cobalt-attack-surface-monitoring) is a commercial [external attack surface management](https://cybersectools.com/categories/external-asm) solution by [Cobalt](https://cybersectools.com/companies/cobalt). [S3BucketList](https://cybersectools.com/tools/s3bucketlist) is a free [external attack surface management](https://cybersectools.com/categories/external-asm) solution. Features, integrations, deployment and the company behind each one, side by side.

Need the answer fast? [Best Attack Surface Management Solutions for Business](https://cybersectools.com/shortlists/best-attack-surface-solutions) picks Palo Alto Networks Cortex Xpanse, Microsoft Defender EASM, Mandiant Attack Surface Management and 4 more.

## Side-by-side comparison

| | Cobalt Attack Surface Monitoring | S3BucketList |
|---|---|---|
| Pricing model | Commercial | Free |
| Category | External Attack Surface Management | External Attack Surface Management |
| Verified | No | No |
| Deployment type | Cloud | Cloud |
| Company size fit | SMB, Mid-Market, Enterprise | Startup, SMB, Mid-Market, Enterprise |
| GitHub stars | – | 124 |
| Last commit | – | Aug 2025 |
| Company | Cobalt | – |
| Headquarters | – | – |

### Use cases and capabilities

| | Cobalt Attack Surface Monitoring | S3BucketList |
|---|---|---|
| Reconnaissance | Yes | Yes |
| Enumeration | – | Yes |
| Browser Security | – | Yes |
| S3 | – | Yes |
| AWS | – | Yes |

### Core features

**Cobalt Attack Surface Monitoring**

7 features listed. Sign in on the page to see them.

**S3BucketList**

No features listed.

### Integrations

**Cobalt Attack Surface Monitoring**

15 integrations listed. Sign in on the page to see them.

**S3BucketList**

No integrations listed.

## Which one fits you

Based on what each listing shows: deployment, company size, price and open source.

- [S3BucketList](https://cybersectools.com/tools/s3bucketlist) fits if you are a startup, you need a free product and you want an open-source product.

## Cobalt Attack Surface Monitoring vs S3BucketList FAQ

Common questions when comparing Cobalt Attack Surface Monitoring vs S3BucketList for external attack surface management.

### What is the difference between Cobalt Attack Surface Monitoring and S3BucketList?

**Cobalt Attack Surface Monitoring**: Continuous external asset discovery and monitoring with daily domain scans. Built by Cobalt.

**S3BucketList**: A Chrome extension that automatically detects and lists Amazon S3 buckets while browsing websites.

The table above shows where their features, integrations, deployment and company size fit differ.

### Who makes Cobalt Attack Surface Monitoring and S3BucketList?

**Cobalt Attack Surface Monitoring** is made by Cobalt. **S3BucketList** is open-source with 124 GitHub stars. The vendor behind a product decides its roadmap, support, and longevity, so check each company's profile before you commit.

### Is Cobalt Attack Surface Monitoring a good alternative to S3BucketList?

Often, yes. Cobalt Attack Surface Monitoring and S3BucketList are both External Attack Surface Management products, and both cover Reconnaissance. Key differences: Cobalt Attack Surface Monitoring is Commercial while S3BucketList is Free, S3BucketList is open-source. Use the table above to see where features, deployment and company size fit differ.

## Related comparisons

- [Cobalt Attack Surface Monitoring vs Censys Attack Surface Management](https://cybersectools.com/compare/censys-attack-surface-management-vs-cobalt-attack-surface-monitoring)
- [Cobalt Attack Surface Monitoring vs Intruder Attack Surface Management](https://cybersectools.com/compare/cobalt-attack-surface-monitoring-vs-intruder-attack-surface-management)
- [Cobalt Attack Surface Monitoring vs Matos Automated Attack Surface Management](https://cybersectools.com/compare/cloudmatos-automated-attack-surface-management-vs-cobalt-attack-surface-monitoring)
- [S3BucketList vs Censys Attack Surface Management](https://cybersectools.com/compare/censys-attack-surface-management-vs-s3bucketlist)
- [S3BucketList vs Intruder Attack Surface Management](https://cybersectools.com/compare/intruder-attack-surface-management-vs-s3bucketlist)
- [S3BucketList vs Matos Automated Attack Surface Management](https://cybersectools.com/compare/cloudmatos-automated-attack-surface-management-vs-s3bucketlist)

## Alternatives to each

- [See all Cobalt Attack Surface Monitoring alternatives](https://cybersectools.com/alternatives/cobalt-attack-surface-monitoring)
- [See all S3BucketList alternatives](https://cybersectools.com/alternatives/s3bucketlist)

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Source: https://cybersectools.com/compare/cobalt-attack-surface-monitoring-vs-s3bucketlist

For AI agents: each product above has its own Markdown page (add .md to its URL, for example https://cybersectools.com/tools/cobalt-attack-surface-monitoring.md). Every CybersecTools shortlist is listed at https://cybersectools.com/shortlists.md.

More on Cobalt Attack Surface Monitoring and S3BucketList: 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=compare-md