IP Address: 205.220.183.242 ⚠ Network Confounder

⚠ Network Confounder Detected: Proofpoint Email Security
Proofpoint network identifier

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

Geolocation Information

Country:: US United States
Coordinates:: 37.751, -97.822

WHOIS Information

Network Name:: PROOF
CIDR:: 205.220.160.0/19
Owner:: Proofpoint, Inc.
Org ID:: PROOF
Address:: 925 W Maude Ave, Sunnyvale, CA 94085
Reverse DNS:: mx0b-0065c301.pphosted.com
Last updated: 2/5/2026

Analysis

This IP was first observed on December 4, 2024 and most recently on July 9, 2025. It has been associated with 3 failed authentication events affecting 3 messages, representing low but recurring activity. The IP belongs to PROOF (Proofpoint, Inc.), a network with activity associated with United States. One other IP in the same /24 subnet (205.220.183.*) also appears in this dataset.

Failures Detected from this IP

Showing 1-3 of 3 failures, affecting 3 messages

Date ▼	Messages
7/9/2025	1
7/2/2025	1
12/4/2024	1

External Reputation Lookups

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

AbuseIPDB Cisco Talos Project Honey Pot GreyNoise VirusTotal Shodan Censys Spamhaus

Nearby IPs

Other IPs in the 205.220.183.0/24 range observed failing DMARC:

205.220.183.129 (14 failures)