Sh4meful DMARC Spoof Detection
IP Address: 159.183.224.102
Twilio SendGrid is a cloud-based Email Service Provider (ESP), or Mail Transfer Agent (MTA). It operates as a high-volume, cloud-based SMTP service to send, receive, and relay both transactional and marketing emails. These signals could be indicative of a failure during legitimate sends (through Sendgrid), or could be signal of a spam/spoof attempt using their service which is common enough we're not treating this as a confounder.
About this Data
▶The data here is from DMARC analysis for domains I administer, drawn from a larger dataset (comprising millions of authentication records and messages). These entries are from email attempts that failed both SPF and DKIM (and there are often alignment issues - hidden here). In many cases, these failures indicate unauthorized use of the domain name, and are commonly associated with spoofing, phishing, or other abusive mail activity.
Geolocation Information
- Country:
- US United States
- Coordinates:
- 37.751, -97.822
WHOIS Information
- Network Name:
- TWILI-11
- CIDR:
159.183.0.0/16- Reverse DNS:
-
s.wfbtzhss.outbound-mail.sendgrid.net
Last updated: 2/5/2026
Failures Detected from this IP
Showing 1-24 of 24 (failures, affecting 286 messages)| Date ▲ | Messages |
|---|---|
| 3/6/2024 | 1 |
| 3/16/2024 | 1 |
| 9/12/2024 | 2 |
| 1/8/2025 | 9 |
| 1/17/2025 | 13 |
| 2/14/2025 | 56 |
| 2/26/2025 | 95 |
| 2/28/2025 | 27 |
| 3/12/2025 | 5 |
| 3/14/2025 | 1 |
| 3/19/2025 | 8 |
| 3/26/2025 | 1 |
| 3/28/2025 | 12 |
| 4/18/2025 | 12 |
| 4/30/2025 | 3 |
| 5/7/2025 | 18 |
| 5/16/2025 | 4 |
| 6/6/2025 | 3 |
| 6/18/2025 | 1 |
| 6/19/2025 | 9 |
| 6/26/2025 | 2 |
| 7/23/2025 | 1 |
| 8/22/2025 | 1 |
| 9/23/2025 | 1 |