51.161.37.183📋 Copy

# IP INTELLIGENCE BRIEFING: 51.161.37.183

Classification: Moderate Risk | Status: Requires Monitoring

---

## EXECUTIVE SUMMARY

IP 51.161.37.183 presents a moderate security risk (Score: 40) operating within a high-abuse-density subnet. The address is associated with OVH cloud infrastructure in Montreal, Canada, resolving to the Ahrefs domain. While no active threat indicators were observed, the surrounding /24 subnet demonstrates elevated abuse density (0.7656) with 196 malicious siblings out of 208 active peers.

---

## INFRASTRUCTURE PROFILE

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## THREAT ASSESSMENT

Current Risk Score: 40 (Moderate)

Threat Indicators: None detected

• No known attacker status
• No Tor exit node activity
• No spam source classification
• Zero blacklist entries
• No campaign associations

Network Classification: Cloud hosting environment with firewalled services. The IP exhibits no open ports or active service signatures in recent observations.

---

## NETWORK CONTEXT

Subnet Analysis (51.161.37.0/24):

• Abuse Density: 0.7656 (High)
• Total Siblings: 256
• Active Siblings: 208
• Threat Siblings: 196
• Inherited Risk: 30

The surrounding /24 subnet demonstrates significant abuse concentration, with 196 IPs flagged as threats. This contextual data suggests the IP may be operating in a compromised or shared hosting environment.

---

## OBSERVATION HISTORY

Signal Count: 22 observations recorded

Recent activity shows consistent cloud hosting classification with OVH provider attribution. DNS resolution maintained to proxy-ca005-san183.ahrefs.net. No persistent malicious behavior observed across the observation window, though the subnet's high abuse density warrants continued monitoring.

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## DNS & SERVICE ANALYSIS

PTR Record: proxy-ca005-san183.ahrefs.net

Forward Resolution: Confirmed (ahrefs.net domain)

SSL/TLS: None detected

Open Ports: None detected

The forward resolution confirms the IP resolves to an Ahrefs domain, consistent with the organization's cloud hosting operations.

---

## CONTROL PLANE INTELLIGENCE

• BGP Prefix: 51.161.0.0/17
• Route Stability: Unstable (isRouteStable: false)
• DNSBL Listings: 1 of 8 lists
• RPKI State: Not verified
• IRR Consistency: Not verified

---

## RECOMMENDED ACTIONS

Based on the risk profile, the following firewall rules are recommended:

iptables:

```

iptables -A INPUT -s 51.161.37.183 -j DROP

```

nftables:

```

nft add rule inet filter input ip saddr 51.161.37.183 drop

```

nginx:

```

deny 51.161.37.183;

```

Cloudflare WAF:

```json

{

"description": "Block 51.161.37.183 — IPDebrief risk score 40",

"action": "block",

"filter": {"expression": "ip.src eq 51.161.37.183"}

}

```

AWS WAF:

```json

{

"Addresses": ["51.161.37.183/32"],

"Description": "IPDebrief risk 40"

}

```

---

## ANALYST NOTES

The IP resolves to Ahrefs infrastructure but operates within a high-abuse-density subnet. While the specific address shows no direct threat indicators, the contextual abuse density (196 threat siblings) suggests potential for lateral threats or shared infrastructure compromise. Recommendation: Block at perimeter controls, monitor for lateral movement if access is granted.

Threat Persistence: No persistent malicious activity detected

Campaign Association: None

Correlated IPs: 0

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