51.161.37.201📋 Copy

## IP INTELLIGENCE BRIEFING: 51.161.37.201

EXECUTIVE SUMMARY

IP address 51.161.37.201 is a cloud compute resource hosted on OVH infrastructure in Montreal, Canada. The IP presents a moderate risk profile (score: 50) with evidence of recent blacklist activity and operates within a high-abuse density subnet (76.95%). The address is associated with Ahrefs domain infrastructure but shows no active malicious indicators or known campaign affiliations.

OWNERSHIP & INFRASTRUCTURE

• ASN: 16276 (OVH SAS)
• Organization: Dmytro, Ahrefs Pte Ltd
• Netblock: 51.161.37.0/24
• Registration: ARIN
• Infrastructure Type: Cloud compute / Hosting provider
• DNS Resolution: proxy-ca005-san201.ahrefs.net (Ahrefs)

GEOSPATIAL DATA

• Country: Canada (CA)
• Region: Quebec (QC)
• City: Montreal
• Accuracy Radius: 3,000 km
• GeoConsensus: Validated across multiple sources

THREAT INDICATORS & REPUTATION

• Overall Risk Score: 50 (Moderate Risk)
• Abuse Confidence Score: Not available
• Known Attacker: No
• Spam Source: No
• Tor Exit Node: No
• Blacklist Status: 0 explicit blacklists
• DNSBL Listings: 1 of 8 total lists
• Known Campaigns: None identified

NETWORK CLASSIFICATION

• Provider: OVH (Cloud hosting provider)
• Hosting: Yes
• CDN: No
• VPN: No
• Proxy: No
• Mobile/Residential: No

SUBNET CONTEXT (51.161.37.0/24)

• Abuse Density: 76.95% (HIGH ABUSE CLASSIFICATION)
• Subnet Risk Score: 30 (inherited)
• Total Siblings: 256
• Active Siblings: 214
• Threat Siblings: 197
• Risk Distribution: 99 medium, 1 low, 0 high

OBSERVATION HISTORY (21 Total Signals)

Recent activity includes:

• June 29, 2026: Multiple blacklist listings detected (max severity: high)
• June 29, 2026: DNS resolution confirmed to ahrefs.net with valid CAA records
• June 20, 2026: Geolocation data from Cymru indicating Canada
• June 20, 2026: Subnet abuse classification: high_abuse
• Operator Score: 0.2174 (Minimal)

RELATIONSHIP ANALYSIS

• Total Relationships: 33
• Primary Association: OVH-CUST-281059684 (multiple network relationships)
• Network Classification: Same network associations dominate relationship graph

SECURITY ACTIONS RECOMMENDATION

Firewall Rules for Blocking:

• iptables: `iptables -A INPUT -s 51.161.37.201 -j DROP`
• nftables: `nft add rule inet filter input ip saddr 51.161.37.201 drop`
• nginx: `deny 51.161.37.201;`
• pfSense: `51.161.37.201/32`
• Cloudflare WAF: Block IP with expression `ip.src eq 51.161.37.201`
• AWS WAF: Address `51.161.37.201/32`

ANALYST NOTES

The IP operates within an OVH-managed subnet exhibiting high abuse density. While the address resolves to legitimate Ahrefs infrastructure and shows no active threat indicators, the subnet context and recent blacklist activity warrant defensive blocking. The moderate risk score reflects the IP's position within a high-abuse cloud hosting environment rather than confirmed malicious activity. SOC teams should monitor for related IPs within the 51.161.37.0/24 range and maintain block lists at the subnet level if threat correlation persists.

---

*Report generated: 2026-06-29*

*Source: IPDebrief Intelligence Platform*

This summary was generated by AI and may contain inaccuracies. Verify critical details independently.