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

IP Address: 103.197.242.100

Newly observed. IP address 103.197.242.100 is registered to COGETEL Ltd No. 44, Samdech Decho Hun Sen Blvd, Chakangre Krom Commune and geolocates to Cambodia. It was observed in sh4meful's dataset on July 10, 2026. Over the observation window, it has failed DMARC alignment once, targeting one sender domain. Its reverse DNS resolves to cogetel-100-242-197-103.online.com.kh. Network context: this address sits within Cogetel (COGETEL Ltd No. 44, Samdech Decho Hun Sen Blvd, Chakangre Krom Commune), a network sh4meful has observed producing 11 failures across 10 distinct IPs during the same window.

Failure Activity Over Time

Peak activity was observed in the week of July 6, 2026 with 3 failures recorded. Activity in the most recent 30-day window increased sharply compared with the prior period (3 vs 0 failures).

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:
KH Cambodia
Coordinates:
13, 105
WHOIS Information
Network Name:
Cogetel
CIDR:
103.197.242.0/24
Owner:
COGETEL Ltd No. 44, Samdech Decho Hun Sen Blvd, Chakangre Krom Commune
Reverse DNS:
cogetel-100-242-197-103.online.com.kh
Last updated: 7/11/2026

Analysis

This IP generated 3 messages that triggered DMARC failures on July 10, 2026, all within a single day. Every message observed from this source failed both SPF and DKIM verification. Receiving mail providers applied a reject disposition, refusing delivery outright.

The reverse DNS record resolves to cogetel-100-242-197-103.online.com.kh. 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 Cambodia, on infrastructure operated by COGETEL Ltd No. 44, Samdech Decho Hun Sen Blvd, Chakangre Krom Commune. Abuse-reporting channels exist in this jurisdiction but historical response rates are inconsistent, meaning remediation is more often handled through receiver-side blocking than provider-side takedown.

The address is registered to COGETEL Ltd No. 44, Samdech Decho Hun Sen Blvd, Chakangre Krom Commune (Cogetel). 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 Cogetel network, 10 distinct IPs have been associated with 11 authentication failures over 18 observed messages, spanning 1 country. The failure pattern suggests a mix of abuse sources on this network.

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 reject action is doing its job.

Your DMARC policy posture matters more than any IP-level response here. The enforcement action applied to this mail indicates your policy is already providing protection. Maintaining p=reject across all your domains 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 COGETEL Ltd No. 44, Samdech Decho Hun Sen Blvd, Chakangre Krom Commune is listed in APNIC WHOIS records, though response rates from this jurisdiction are inconsistent.

Failures Detected from this IP
Showing 1-1 of 1 failures, affecting 3 messages
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.