Passive DNS records
Current A, AAAA, MX, NS, TXT, CNAME, CAA and DNSKEY records, resolved at lookup time.
DNS History Lookup Past resolutions and current DNS records.
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Output
How this check works · illustration
See which addresses a domain has resolved to, from AlienVault OTX passive DNS, next to its current A, AAAA, MX, NS, TXT, CNAME and CAA records. Use DNS history to spot attacker infrastructure pivots, shared hosting, and suspicious domain moves during SOC triage.
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Capabilities
Signals for your investigation, with their context.
IP history
Every address the domain has resolved to, and when.
Infrastructure pivots
Hostnames that shared an address, to map related infrastructure.
Applications
Use cases to evaluate first.
Threat hunting
Pivot from one domain to the hosts that shared its addresses.
Incident response
Date when a domain moved to malicious infrastructure.
Brand monitoring
Check where your domains resolve today and where they resolved before.
Due diligence
Review a domain’s past before you acquire it.
FAQ
Frequently asked questions.
How far back does DNS history go?
As far back as AlienVault OTX passive DNS observed the domain. Each past resolution shows the first and last dates it was seen; we keep no archive of our own beyond that.
What DNS record types do you track?
Current records: A, AAAA, MX, NS, TXT, CNAME, CAA and DNSKEY, plus the DMARC, MTA-STS, TLS-RPT and BIMI TXT records. Past resolutions are the record types passive DNS observed, mostly A, AAAA and CNAME.
How can DNS history help with threat hunting?
Attackers reuse infrastructure. Domains that shared an address with a known-bad host are worth checking next.
Where does the DNS history come from?
From AlienVault OTX passive DNS, normalized into hostname, address, record type, first seen and last seen.
New to the term? Read the glossary definition.
Explore
Related tools and pages.
Test it with your own indicators.
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