Investigating Phishing Email Incident

import email
from email import policy

with open("phishing_sample.eml", "rb") as f:
    msg = email.message_from_binary_file(f, policy=policy.default)

# Extract key headers
print(f"From: {msg['From']}")
print(f"Return-Path: {msg['Return-Path']}")
print(f"Reply-To: {msg['Reply-To']}")
print(f"Subject: {msg['Subject']}")
print(f"Message-ID: {msg['Message-ID']}")
print(f"X-Originating-IP: {msg['X-Originating-IP']}")

# Parse Received headers (bottom-up for true origin)
for header in reversed(msg.get_all('Received', [])):
    print(f"Received: {header[:120]}")

# Check authentication results
print(f"Authentication-Results: {msg['Authentication-Results']}")
print(f"DKIM-Signature: {msg.get('DKIM-Signature', 'NONE')[:80]}")

import requests

# Submit URL to URLScan.io
url_to_scan = "https://evil-login.example.com/office365"
response = requests.post(
    "https://urlscan.io/api/v1/scan/",
    headers={"API-Key": "YOUR_KEY", "Content-Type": "application/json"},
    json={"url": url_to_scan, "visibility": "unlisted"}
)
scan_id = response.json()["uuid"]
print(f"Scan URL: https://urlscan.io/result/{scan_id}/")

# Check VirusTotal for URL reputation
import vt
client = vt.Client("YOUR_VT_API_KEY")
url_id = vt.url_id(url_to_scan)
url_obj = client.get_object(f"/urls/{url_id}")
print(f"VT Score: {url_obj.last_analysis_stats}")
client.close()

import hashlib

# Calculate file hashes
with open("attachment.docx", "rb") as f:
    content = f.read()
    md5 = hashlib.md5(content).hexdigest()
    sha256 = hashlib.sha256(content).hexdigest()

print(f"MD5: {md5}")
print(f"SHA256: {sha256}")

# Submit to MalwareBazaar for lookup
response = requests.post(
    "https://mb-api.abuse.ch/api/v1/",
    data={"query": "get_info", "hash": sha256}
)
print(response.json()["query_status"])

index=email sourcetype="o365:messageTrace"
(SenderAddress="attacker@evil-domain.com" OR Subject="Urgent: Password Reset Required"
 OR MessageId="<phishing-message-id@evil.com>")
earliest=-7d
| stats count by RecipientAddress, DeliveryStatus, MessageTraceId
| sort - count

import requests

headers = {"Authorization": f"Bearer {access_token}"}
params = {
    "$filter": f"subject eq 'Urgent: Password Reset Required' and "
               f"receivedDateTime ge 2024-03-14T00:00:00Z",
    "$select": "sender,toRecipients,subject,receivedDateTime",
    "$top": 100
}
response = requests.get(
    "https://graph.microsoft.com/v1.0/users/admin@company.com/messages",
    headers=headers, params=params
)
messages = response.json()["value"]
print(f"Found {len(messages)} matching messages")

index=proxy dest="evil-login.example.com" earliest=-7d
| stats count, values(action) AS actions, latest(_time) AS last_access
  by src_ip, user
| lookup asset_lookup_by_cidr ip AS src_ip OUTPUT owner, category
| sort - count
| table user, src_ip, owner, actions, count, last_access

index=proxy dest="evil-login.example.com" http_method=POST earliest=-7d
| stats count by src_ip, user, url, status

# Microsoft 365 Compliance Search and Purge
New-ComplianceSearch -Name "Phishing_Purge_2024_0315" `
    -ExchangeLocation All `
    -ContentMatchQuery '(From:attacker@evil-domain.com) AND (Subject:"Urgent: Password Reset Required")'

Start-ComplianceSearch -Identity "Phishing_Purge_2024_0315"

# After search completes, execute purge
New-ComplianceSearchAction -SearchName "Phishing_Purge_2024_0315" -Purge -PurgeType SoftDelete

# Force password reset for impacted users
$impactedUsers = @("user1@company.com", "user2@company.com")
foreach ($user in $impactedUsers) {
    Set-MsolUserPassword -UserPrincipalName $user -ForceChangePassword $true
    Revoke-AzureADUserAllRefreshToken -ObjectId (Get-AzureADUser -ObjectId $user).ObjectId
}

| makeresults
| eval incident_id="PHI-2024-0315",
       reported_time="2024-03-15 09:12:00",
       sender="attacker@evil-domain[.]com",
       subject="Urgent: Password Reset Required",
       url="hxxps://evil-login[.]example[.]com/office365",
       recipients_count=47,
       clicked_count=5,
       credentials_submitted=2,
       emails_purged=47,
       passwords_reset=2,
       domains_blocked=1,
       disposition="True Positive - Credential Phishing Campaign"
| table incident_id, reported_time, sender, subject, url, recipients_count,
        clicked_count, credentials_submitted, emails_purged, passwords_reset, disposition