SANS ISC: Phishing message to the ISC handlers email distro

• SANS Site Network
  • Current Site
  • SANS Internet Storm Center
  • Other SANS Sites Help
  • Graduate Degree Programs
  • Security Training
  • Security Certification
  • Security Awareness Training
  • Penetration Testing
  • Industrial Control Systems
  • Cyber Defense Foundations
  • DFIR
  • Software Security
  • Government OnSite Training

SANS ISC InfoSec Forums

Introduction

The ISC handlers email distro gets plenty of spam and phishing emails on a daily basis.  Most of these are filtered so they never make it to the inbox; however, every once in a while one gets through.

Today's diary reviews an example of a phishing email from our inbox on Tuesday 2021-02-09.

Shown above:  Email headers from the phishing message.

The email

As shown in the previous image, the sending address had been spoofed to look like it came from administrator@sans.isc.edu.  But the message actually came to our mail server from 165.232.128[.]118.  That much we can confirm, because it was the most recent Received: from line before it hit our mail server.  Anything else can be spoofed.  Based on the only other Received: from line, this message might have originated from 69.12.85[.]209, but that line could have been added to confuse analysts.

Shown above:  Screenshot of the phishing messaged when viewed in the Thunderbird email client.

The phishing message has a URL to hxxps://soberlab[.]ca/sl.html?email=[phishing recipient's email address].  The domain oberlab[.]ca seems like it is hosting a legitimate website, and that legitimate website may have been compromised to host the phishing URL.

Shown above:  Opening link from the phishing message in a web browser.

Phishing traffic

Shown above:  Traffic from viewing the email link filtered in Wireshark.

The HTTPS link from the email redirects to a phishing page at hxxp://aromatee[.]com[.]au/inc/mail.php.  Like the previous URL, this one looks like it's hosted on a legitimate domain using a server that's been compromised to host a phishing URL.  I entered a fake password, and the data was sent over HTTP back to the server.

Shown above:  HTTP POST request with the fake password I entered.

Final words

These types of emails are all too common, and they're remarkably cost-effective.  While most of you wouldn't fall for it, people are fooled by similar messages.  Therefore, phishing will remain a viable social engineering technique.

A sanitized version of the email shown in this diary, along with a pcap of traffic to the associated phishing page, can be found here.

---
Brad Duncan
brad [at] malware-traffic-analysis.net