52.123.251.21
52.123.251.21 is an IPv4 address operated by Microsoft Corporation (AS8075), geolocated to Redmond, United States. It belongs to datacenter or hosting infrastructure. As of October 30, 2026, IPDebrief rates it Low Risk (25/100); no anonymizing service was detected.
The IP address 52.123.251.21 was attributed to Microsoft Corporation (ASN 8075) within the 52.120.0.0/14 block, registered in Redmond, Washington. Ownership records indicated the host functioned as a Web Server, with active listening on ports 80, 443, and 8443. TLS certificate analysis confirmed issuance by DigiCert Inc for Outlook.com and Microsoft Corporation domains.
The assessment assigned a Low Risk reputation score of 25. However, intelligence gathered noted signal contradictions between claimed geolocation and physical RTT measurements, recording an average response time of 31.4ms against a minimum possible 127.6ms for the reported distance. The address was listed on one of eight observed DNS blacklists. Neighborhood analysis classified the subnet as mixed with an abuse density of 0.2162, including 24 threat siblings among 110 active siblings. Behavioral logs showed no active attacker status, but the threat actor classification
This summary was generated by AI and may contain inaccuracies. Verify critical details independently.
🏢 Ownership & Registration
| Organization | Microsoft Corporation |
| ASN | AS8075 |
| Network Name | MSFT |
| CIDR Block | 52.120.0.0/14 |
| RIR | ARIN |
| Country | United States |
| Abuse Contact | Available via RDAP |
🌐 DNS Intelligence
| PTR Record | No PTR |
| Forward Confirmed | No — PTR hostname does not resolve back to this IP (weak signal) |
🔐 DNS Hygiene
| Hygiene Score | 40% (Fair) |
| SPF | 5/9 domains |
| DMARC | 6/9 domains |
| FCrDNS | Not verified |
| DNSSEC | Not signed |
| CAA | Not configured |
| Domains Checked | 9 domains |
☁️ Network Classification
| Infrastructure | Infrastructure / Datacenter |
| Service Purpose | Web Server |
| Network Tier | Hosting — Infrastructure provider without advanced routing |
🔌 Services & Open Ports
| Port | Service | Protocol | Banner |
|---|---|---|---|
| 80 | http | tcp | — |
| 443 | https | tcp | — |
| 8443 | https-alt | tcp | — |
| Closed Ports | 22, 25, 3389, 8080 (3 open / 7 scanned) | ||
| Server | Web server detected |
| HTTP Title | — |
🔐 TLS Certificate
| SANs | outlook.com*.hotmail.com*.internal.outlook.com*.live.com*.office.com*.office365.com*.outlook.com*.outlook.office365.comattachment.outlook.live.netattachment.outlook.office.net |
| Valid From | 2026-06-26T00:00:00+00:00 |
| Valid Until | 2027-01-10T23:59:59+00:00 |
| TLS Protocol | Tls13 |
| Cipher Suite | TLS_AES_256_GCM_SHA384 |
| Signature Algorithm | sha256RSA |
| Validity Period | 198 days |
🛡️ Public Network Snapshot
| Origin ASN | AS8075 |
| Network Prefix | 52.120.0.0/14 |
| Route mapping | Found |
| HSTS | Not detected |
| CSP | Not detected |
| HTTP/2 | Enabled |
🎯 Confidence Breakdown
Per-dimension confidence scores based on source diversity and data freshness
| Dimension | Score | Sources | Observations |
|---|---|---|---|
| threat | 20% | 2 | 4 |
| routing | 8% | 1 | 1 |
| services | 35% | 2 | 5 |
| ownership | 17% | 2 | 3 |
| reputation | 18% | 1 | 4 |
| geolocation | 31% | 2 | 6 |
| Overall | 21% | 10 | 23 |
| Data Coherence | Mostly Consistent (80%) — 1 contradiction(s) |
| Attribution | Low (35%) |
| OwnershipFCrDNSGeo ConsensusGeo PlausibleIRR MatchRPKI Valid |
📅 Observation Timeline 🔄 Live
| First Seen | 2026-09-28 21:46:40 UTC |
| Last Seen | 2026-10-30 22:59:03 UTC |
| Profile Built | 2026-10-30 23:10:17 UTC |
| Data Freshness | Live |
| Signal Types | 24 |
| Total Observations | 51 |
Full dossier details are available via our API.
❓ Frequently Asked Questions About 52.123.251.21
Who owns the IP address 52.123.251.21?
52.123.251.21 is registered to Microsoft Corporation. The address falls within the 52.120.0.0/14 network block. Registration is held at ARIN.
Where is 52.123.251.21 located?
Geolocation data places 52.123.251.21 in Redmond, WA, United States. The local time zone is America/Los_Angeles. IP geolocation is approximate and indicates the network's registered or routed location rather than a precise physical address.
Is 52.123.251.21 malicious or safe?
52.123.251.21 currently carries a low risk assessment, meaning no significant threat indicators have been observed. This assessment is generated from continuously collected signals and can change over time.
What ports are open on 52.123.251.21?
Responsive ports observed on 52.123.251.21 include 80, 443, 8443. Port visibility reflects the most recent scan and may change as the host's configuration or firewall rules change.
Is 52.123.251.21 a VPN, proxy, or data center address?
52.123.251.21 is classified as cloud infrastructure and hosting infrastructure based on network ownership and behavioural analysis.