T1598 – Phishing for Information (Proofpoint Detection)

Proofpoint Alert Details

Alert ID: PROOFPOINT-PHISH-INFO-7842
Alert Time: 2024-02-10 10:15:22 EST
Severity: HIGH (82/100)
Source: Proofpoint Targeted Attack Protection (TAP)
Rule: “Credential Phishing Attempt Detected”
MITRE ATT&CK: T1598 – Phishing for Information

Alert Details:

Email Analysis Report:

Sender: noreply@adp-payroll[.]net

Reply-To: support@payroll-verify[.]com

Subject: “ACTION REQUIRED: Your Q1 Payroll Statement Requires Verification”

Recipients: 47 employees (Finance, HR, Executive)

Time: 2024-02-10 10:05 EST

Email Headers:

– Return-Path: bounce@mailing-service[.]ru

– SPF: FAIL (sender IP 185.143.221[.]45 not authorized)

– DKIM: none

– DMARC: FAIL

– X-Originating-IP: 185.143.221[.]45

Email Body:

“Dear Employee,

Our records indicate that your Q1 payroll statement contains discrepancies that require immediate verification. Failure to verify within 24 hours will result in delayed salary processing.

Please click the link below to access your statement and verify your information:

https://adp-verify-portal[.]com/secure/statement

This is a secure link that expires in 24 hours.

Thank you,

ADP Payroll Services”

URL Analysis:

– Domain: adp-verify-portal[.]com

– Registration: 2024-02-09 (1 day ago)

– Registrar: Namecheap

– Hosting IP: 185.143.221[.]45 (Bulgaria)

– URLScan.io: Phishing page mimicking ADP login

– VirusTotal: 48/94 vendors flag as malicious

Attachment: None (link-based phishing)

Threat Intelligence:

– Domain pattern matches known payroll phishing campaign

– IP 185.143.221[.]45 associated with TA569 (credential harvesting)

– Similar emails targeting finance/HR departments nationwide

SOC Investigation Process

StepActionTools UsedFindings
1. Alert ValidationVerify email analysis in ProofpointProofpoint TAP ConsoleConfirmed malicious phishing email
2. URL AnalysisInvestigate phishing domainURLScan.io, VirusTotalDomain hosts ADP credential harvester
3. Recipient IdentificationIdentify all targeted usersProofpoint Logs, AD47 users in Finance, HR, Exec teams
4. Email RemediationQuarantine and remove emailsProofpoint, Exchange OnlineAll 47 emails quarantined; purged from inboxes
5. User NotificationAlert targeted usersEmail, Teams, PhoneAll users notified; no clicks reported
6. Infrastructure BlockingBlock domain and IPPalo Alto, Cisco UmbrellaDomain and IP added to blocklists

Jira Incident Report

Ticket: SOC-2024-050
Summary: T1598 – Payroll-Themed Credential Phishing Campaign
Status: RESOLVED
Resolution: MALICIOUS – Phishing Blocked
Priority: P2 – MEDIUM
Labels: T1598, phishing, credential-harvesting, payroll, proofpoint
Components: Email-Security, Phishing-Response


INCIDENT ANALYSIS REPORT

1. Initial Context:

  • Detection Source: Proofpoint Targeted Attack Protection (TAP).
  • Alert: “Credential Phishing Attempt Detected”.
  • Targets: 47 employees (Finance, HR, Executive).
  • Time: 2024-02-10 10:15 EST.
  • Technique: MITRE ATT&CK T1598 – Phishing for Information.

2. Technical Analysis:

  • Email Details:
  • Sender: noreply@adp-payroll[.]net (spoofed)
  • Subject: “ACTION REQUIRED: Your Q1 Payroll Statement Requires Verification”
  • Theme: Payroll discrepancy requiring immediate action
  • Social Engineering: Urgency (“24 hours”), authority (ADP branding)
  • Infrastructure Analysis:
  • Domain: adp-verify-portal[.]com (registered 2024-02-09)
  • IP: 185.143.221[.]45 (Bulgaria VPS)
  • Hosting: Fake ADP login page with credential harvesting
  • SSL: Let’s Encrypt certificate issued to “ADP Portal”
  • Email Authentication:
  • SPF: FAIL (sender not authorized)
  • DKIM: none
  • DMARC: FAIL
  • Confirmed spoofing attempt
  • Campaign Impact:
  • 47 internal recipients
  • All emails quarantined within 10 minutes of delivery
  • Zero user clicks reported
  • No credentials compromised

3. Investigation Findings:

  • Timeline:

10:05 – Email delivered to 47 users

10:08 – Proofpoint TAP analyzes and flags as malicious

10:10 – Email automatically quarantined

10:15 – SOC alert generated

10:18 – Investigation begins

10:25 – All users notified

10:30 – Domain/IP added to blocklists

10:35 – Takedown request submitted

  • Indicators of Compromise (IoCs):

Email:

– Sender: noreply@adp-payroll[.]net

– Subject: “ACTION REQUIRED: Your Q1 Payroll Statement Requires Verification”

Network:

– Domain: adp-verify-portal[.]com

– IP: 185.143.221[.]45

– URL: hxxps://adp-verify-portal[.]com/secure/statement

4. Containment Actions:

  • Immediate Remediation (10:15-10:30 EST):
  • All 47 emails quarantined via Proofpoint.
  • Purged from user inboxes using Exchange Online.
  • Domain and IP blocked at firewall and DNS.
  • URL added to web proxy blocklist.
  • User Notification (10:25-10:45 EST):
  • All 47 users contacted via email and Teams.
  • Confirmed no users clicked the link.
  • Security awareness reminder sent to department.
  • Takedown Request (10:35 EST):
  • Reported to Namecheap abuse.
  • Reported to hosting provider.
  • Domain suspended within 24 hours.

5. Root Cause Analysis:

  • Primary Cause: External attacker conducting payroll-themed phishing campaign.
  • Contributing Factors:
  1. Employees are frequent targets of payroll-themed attacks.
  2. Spoofed domain closely mimics legitimate ADP communications.

6. Business Impact:

  • Operational Impact: None.
  • Data Exposure: None (no clicks, no credentials compromised).
  • Reputational Impact: None.

7. Remediation & Prevention:

Completed Actions:

  • checkedAll malicious emails removed.
  • checkedInfrastructure blocked.
  • checkedUsers notified and educated.
  • checkedTakedown requests submitted.

Prevention Enhancements:

  • checkedEnhanced Proofpoint rules for payroll-themed emails.
  • checkedAdded “ADP” and “payroll” keywords to impersonation protection.
  • checkedScheduled department-specific phishing simulation.

8. Conclusion:

This incident involved a targeted payroll-themed phishing campaign attempting to harvest employee credentials. Proofpoint’s detection and automated quarantine prevented any user interaction. No compromise occurred.

Closure Rationale: Phishing blocked; no user compromise; infrastructure taken down.

Analyst: [Walter White], SOC Analyst
Date: 2024-02-10 11:30 EST

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