54.39.136.160📋 Copy

# IP Intelligence Briefing: 54.39.136.160/32

## Executive Summary

Intellectually assessed as a moderate-risk (40) cloud hosting infrastructure address associated with OVH CDN infrastructure. The IP resolves to the Ahrefs.net domain and operates within a high-abuse density subnet (0.7031), though the address itself shows no direct threat indicators. No open services detected; firewall rules recommended for defensive hardening.

## Ownership and Network Context

• ASN: 16276 (OVH SAS)
• Organization: Dmytro, Ahrefs Pte Ltd
• CIDR Block: 54.39.136.0/24
• Infrastructure Type: CloudCompute, Hosting
• Geolocation: Beauharnois, QC, Canada (CA)
• Network Classification: Cloud infrastructure with firewalled/no services status

## Threat Profile Assessment

Risk Score: 40 (Moderate Risk)

Threat Indicators: None detected

• Is Tor Exit: No
• Is Known Attacker: No
• Is Spam Source: No
• Blacklist Count: 0
• Threat Feeds: None

Control Plane Indicators:

• DNSSEC Valid: Yes
• CAA Records: Present
• Route Stability: Unstable (false)
• DNSBL Listed: 1 of 8 total lists
• Operator Score: 0.2174 (Minimal)

## Subnet Analysis (54.39.136.0/24)

• Abuse Density: 0.7031 (High)
• Classification: high_abuse
• Inherited Risk: 28
• Total Siblings: 256
• Active Siblings: 185
• Threat Siblings: 180

Neighborhood shows elevated abuse activity with 180 threat siblings out of 256 total addresses. Risk distribution within subnet: 82 low, 18 medium, 0 high risk neighbors.

## Historical Observation Analysis

Total Observations: 19 signals tracked

Recent signal timeline indicates:

• June 20, 2026: Abuse density classification established as high_abuse
• June 20, 2026: Provider confirmed as OVH; cloud/hosting infrastructure validated
• June 28, 2026: Minimal operator risk score (0.087)

No evidence of escalating malicious behavior over observation period. Consistent cloud infrastructure classification maintained across signals.

## DNS and Service Analysis

• PTR Hostname: proxy-ca002-san160.ahrefs.net
• Forward Resolution: Confirmed (1 hostname)
• Domain: ahrefs.net
• Open Ports: None detected
• Service Status: Firewalled / No Services

## Recommended Security Actions

Firewall Rules (Immediate)

```bash

# iptables

iptables -A INPUT -s 54.39.136.160 -j DROP

# nftables

nft add rule inet filter input ip saddr 54.39.136.160 drop

```

Web Application Firewall

```nginx

# nginx

deny 54.39.136.160;

# Cloudflare WAF

{"description":"Block 54.39.136.160 — IPDebrief risk score 40","action":"block","filter":{"expression":"ip.src eq 54.39.136.160"}}

# AWS WAF

{"Addresses":["54.39.136.160/32"],"Description":"IPDebrief risk 40"}

```

Network-Specific Rule

```pfsense

54.39.136.160/32

```

## Analyst Notes

The IP address belongs to legitimate cloud infrastructure (Ahrefs/ahrefs.net) but operates within a high-abuse-density OVH subnet. The moderate risk score (40) combined with the subnet's high abuse density warrants blocking at the perimeter, despite lack of direct threat indicators on the specific address. The absence of open services suggests the IP may be used for outbound connections or as a relay endpoint. Monitor for any changes in service discovery or threat indicator emergence.

Classification: Moderate Risk — Block recommended

Last Updated: 2026-06-28

Data Sources: IPDebrief Intelligence Platform

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