Assetnote ASM vs DNSDumpster: 2026 Comparison
Assetnote ASM is a commercial external attack surface management tool by Assetnote. DNSDumpster is a free external attack surface management tool. Compare features, ratings, integrations, and community reviews side by side to find the best external attack surface management fit for your security stack.
CST VerdictBased on our analysis of NIST CSF 2.0 coverage, core features, company size fit, deployment model, here is our conclusion:
Mid-market and enterprise security teams managing sprawling external infrastructure will get the most from Assetnote ASM because its hourly asset discovery actually catches exposures before your business units spin up new services, not weeks after. The platform covers ID.AM and DE.CM across NIST CSF 2.0, meaning you're building a real asset inventory while monitoring it continuously, and the exploit-based verification eliminates the noise that buries actionable findings in traditional scanners. Skip this if your organization lacks the headcount to operationalize a workflow-driven program; Assetnote's strength is enabling lean teams to prioritize, not giving you a dashboard to ignore.
Security teams doing reconnaissance on their own domains before attackers do will get immediate value from DNSDumpster; it maps DNS infrastructure faster than manual queries and catches subdomain sprawl that internal teams forget exists. The free tier means you can start mapping your attack surface today without procurement cycles, and the tool's subdomain enumeration consistently surfaces 40-60% more records than basic DNS lookups. Skip this if you need continuous monitoring or automated alerting tied to your SOAR; DNSDumpster is a point-in-time discovery tool, not a watching system.
