51.161.37.83
IP Intelligence Briefing: 51.161.37.83
Date: June 10, 2026
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**1. Core Profile**
- Risk Score: Moderate (50/100)
- Ownership:
- ISP: OVH (ASN 16276)
- Organization: Dmytro, Ahrefs Pte Ltd (OVH-CUST-281059684)
- Geolocation: Montreal, Canada (geoPlausible: false)
- Threat Indicators: No known malicious activity, no DNSBL listings, no spam/attacker flags.
- Network Role: CloudCompute (OVH-hosted), no CDN/VPN/Proxy.
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**2. Geolocation Anomalies**
- RTT Discrepancy: 27ms RTT for a 6,082km distance (minimum possible: 121.6ms).
- GeoValidation: Inferred location (Montreal, CA) conflicts with distance-based RTT expectations.
- Subnet Abuse: Subnet 51.161.37.0/24 classified as high_abuse (63% abuse density).
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**3. Network Relationships**
- Linked Entities:
- Same network: OVH-CUST-281059684 (256 IPs, 185 active, 162 malicious).
- DNS: PTR hostname `proxy-ca005-san83.ahrefs.net` (Ahrefs domain).
- Subnet Neighbors:
- 100 IPs in 51.161.37.0/24 (78 medium-risk, 22 low-risk).
- Subnet abuse density: 0% (contradicts subnet classification).
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**4. Historical Observations**
- Recent Activity (June 10, 2026):
- Subnet abuse classification updated to "high_abuse."
- DNSSEC invalid (no RRSIG).
- Geo validation flagged as anomalous.
- No TLS/HTTP services detected.
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**5. Threat Assessment**
- Likelihood: No direct malicious campaigns or known attackers.
- Subnet Risk: High abuse density (63%) despite neighbors tool reporting 0% abuse.
- Geolocation: Possible spoofing or misconfigured routing.
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**6. Recommendations**
- Monitor Subnet: Track activity in 51.161.37.0/24 for coordinated threats.
- Verify Geolocation: Investigate RTT anomalies and validate Montreal IP assignment.
- Cloud Security: Ensure OVH-hosted instance has firewall rules and intrusion detection enabled.
- DNSSEC: Validate DNSSEC configuration for `ahrefs.net` to prevent spoofing.
Next Steps: Cross-reference with Ahrefs' network logs and verify subnet abuse density discrepancies.
This summary was generated by AI and may contain inaccuracies. Verify critical details independently.
🏢 Ownership & Registration
| Organization | Dmytro, Ahrefs Pte Ltd |
| ASN | AS16276 |
| Network Name | OVH-CUST-281059684 |
| CIDR Block | 51.161.37.0/24 |
| RIR | ARIN |
| Country | Singapore |
| Abuse Contact | — |
🌐 DNS Intelligence
| PTR | proxy-ca005-san83.ahrefs.net |
| Forward Confirmed | No — PTR hostname does not resolve back to this IP (weak signal) |
| Forward Hostnames | proxy-ca005-san83.ahrefs.net |
🔐 DNS Hygiene
| Hygiene Score | 40% (Fair) |
| SPF | Not configured |
| DMARC | Not configured |
| FCrDNS | Not verified |
| DNSSEC | Valid |
| CAA | Present |
☁️ Network Classification
| Infrastructure | Infrastructure / Datacenter |
| Service Purpose | Firewalled / No Services |
| Network Tier | Hosting — Infrastructure provider without advanced routing |
🔌 Services & Open Ports
| Port | Service | Protocol | Banner |
|---|---|---|---|
| No open ports detected | |||
| Closed Ports | 22, 25, 80, 443, 3389, 8080, 8443 (0 open / 7 scanned) | ||
| Server | — |
| HTTP Title | — |
🔐 TLS Certificate
| SANs | None |
| Valid From | — |
| Valid Until | — |
🎯 Confidence Breakdown
Per-dimension confidence scores based on source diversity and data freshness
| Dimension | Score | Sources | Observations |
|---|---|---|---|
| threat | 34% | 2 | 3 |
| routing | 13% | 1 | 1 |
| services | 15% | 2 | 2 |
| ownership | 15% | 2 | 2 |
| reputation | 23% | 1 | 2 |
| geolocation | 40% | 2 | 3 |
| Overall | 23% | 10 | 13 |
| Data Coherence | Mostly Consistent (80%) — 1 contradiction(s) |
| Attribution | Low (35%) |
| OwnershipFCrDNSGeo ConsensusGeo PlausibleIRR MatchRPKI Valid |
📅 Observation Timeline 🔄 Live
| First Seen | 2026-05-24 00:32:54 UTC |
| Last Seen | 2026-06-28 23:25:38 UTC |
| Profile Built | 2026-06-29 05:28:02 UTC |
| Data Freshness | Live |
| Signal Types | 20 |
| Total Observations | 22 |
Full dossier details are available via our API.