Shame on you, stupid spammers.. Sh4meful  DMARC Spoof Detection

IP Address: 216.47.170.245

Dormant. IP address 216.47.170.245 is registered to Advanced Corporate Network and geolocates to Norwalk, United States. It first appeared in sh4meful's dataset on April 10, 2025 and was most recently observed on July 8, 2025. Over the observation window, it has failed DMARC alignment 8 times, targeting one sender domain. Its reverse DNS resolves to tos-exchange.suffieldct.gov. Network context: this address sits within ACN-BLK-01 (Advanced Corporate Network), a network sh4meful has observed producing 8 failures across 1 distinct IP during the same window.

Failure Activity Over Time

This IP has claimed to send from 1 sender domain monitored by sh4meful. The single targeted domain suggests either a compromised sending source or a spoofing attempt focused on a specific brand.

This page shows DMARC authentication failure data for this IP address. Learn more about this data.

Geolocation Information
Country:
US United States
Region:
Connecticut
City:
Norwalk
Coordinates:
41.136, -73.406
WHOIS Information
Network Name:
ACN-BLK-01
CIDR:
216.47.160.0/19
Owner:
Advanced Corporate Network
Org ID:
ADCN
Address:
192 Naugatuck Ave, Milford, CT 06460
Reverse DNS:
tos-exchange.suffieldct.gov
Last updated: 2/5/2026

Analysis

This IP has generated DMARC authentication failures across 11 messages between April 10, 2025 and July 8, 2025. Every message observed from this source failed both SPF and DKIM verification. Receiving mail providers took no enforcement action beyond reporting, indicating the sending domain's DMARC policy is set to p=none.

The reverse DNS record resolves to tos-exchange.suffieldct.gov. Whether this represents legitimate mail infrastructure depends on whether the hostname aligns with the domains this address is claiming to send on behalf of.

Geolocation places the host in Norwalk, United States, on infrastructure operated by Advanced Corporate Network. Abuse-reporting channels in this jurisdiction are generally responsive, and reports to the network operator can result in timely remediation.

The address is registered to Advanced Corporate Network (ACN-BLK-01). Enterprise-registered addresses that appear in DMARC failure data are typically either compromised hosts on the organization's network or outbound mail relays that are not properly authorized in the domain's SPF record.

Across the wider ACN-BLK-01 network, 1 distinct IP has been associated with 8 authentication failures over 11 observed messages, spanning 1 country. Activity on this network is sparse in this dataset, suggesting isolated rather than systematic abuse.

If your domain appears in the From header of mail from this address, treat it as probable spoofing. Verify that your SPF record does not authorize this host, directly or through nested include mechanisms, and that no DKIM selector you publish has been issued to it. If both checks come back clean, the receiver's none enforcement action is doing its job.

Your DMARC policy posture matters more than any IP-level response here. A p=none policy provides visibility but no enforcement, meaning mail is reported but not blocked. Moving to p=quarantine and then p=reject closes the gap for attackers who manage partial alignment. Domains that remain at p=none long-term tend to be impersonated repeatedly, because the cost to the attacker of attempting is effectively zero.

Blocking this individual address has limited durability: an attacker can rotate to another address in the same /24 subnet at effectively zero cost. More durable responses include monitoring aggregate DMARC reports so new sources are visible as they emerge, tightening SPF to remove overly permissive include chains or +all mechanisms, and ensuring DKIM is signing every legitimate outbound stream so alignment failures are unambiguous. The formal abuse contact for Advanced Corporate Network is listed in ARIN WHOIS records, and timely remediation is achievable through that channel.

Failures Detected from this IP
Showing 1-8 of 8 failures, affecting 11 messages
Date โ–ผ Messages
7/8/2025 2
7/2/2025 3
6/30/2025 1
6/25/2025 1
6/19/2025 1
6/10/2025 1
4/22/2025 1
4/10/2025 1
External Reputation Lookups

Look up this IP in external threat intelligence and reputation databases (opens in new tab):

Recommended Action

If this IP appears in your own DMARC reports, treat it as an unauthorized sender unless you have specifically verified it as a legitimate service you use. Ensure your DMARC policy is at p=quarantine or p=reject to prevent delivery of messages this IP claims to send from your domain. If you're new to DMARC, our complete guide walks through the mechanics.