// BTLO  ·  Incident Response

Insider Brett

BTLO Easy Wireshark

Scenario

Initech’s CISO, Milton Waddams (CISSP, CISM), was the victim of a blackmail attempt requesting payment of 50 BTC. An IT contractor named Brett Hart is the suspected culprit — operating as a standard user. Artefacts were collected from a folder called “Hacking” on his Kali Virtual Machine. Milton assured investigators the environment employs all best practices and is “unhackable.”

Spoiler: it was not unhackable.


Methodology

Reconnaissance — Nmap Scan

The first artefact is scan.txt — an Nmap output file. The header reveals the full command and timestamp:

# Nmap 7.94SVN scan initiated Thu Apr 11 07:10:24 2024 as:
nmap -sS --script *smb*,*ldap* -sV --version-all -T5 -oN scan.txt 192.168.25.0/24

Key flags used:

  • -sS — TCP SYN stealth scan
  • --script *smb*,*ldap* — runs all SMB and LDAP NSE scripts (enumeration + brute force)
  • -sV --version-all — aggressive service version detection
  • -T5 — maximum timing template (fastest, noisiest)
  • -oN scan.txt — normal output to file

The first responding host returned MAC address 00:50:56:F4:3C:76 — a VMware OUI, confirming this is a virtualised environment.

Domain Enumeration — LDAP Scripts

The LDAP scripts successfully enumerated the Active Directory domain:

dnsHostName: voenmeh-d0f286a.initech.local
ldapServiceName: initech.local:voenmeh-d0f286a$@INITECH.LOCAL
  • Domain: initech.local
  • Domain Controller hostname: voenmeh-d0f286a.initech.local

    Credential Brute Force — SMB Scripts

The smb-brute NSE script attempted credential stuffing against SMB. Results:

guest:<blank>         => Valid credentials, account disabled
it:football           => Valid credentials
jane-fleck:<blank>    => Valid credentials, account disabled
milton-waddams:password => Valid credentials

Two enabled accounts had passwords successfully guessed:

  • it — password: football
  • milton-waddams — password: password

Milton’s password being literally password on an “unhackable” environment is the critical failure point. The SMB session data confirms Milton was actively logged in at the time of the scan:

Users logged in:
  INITECH\Milton-Waddams since 2024-04-11T10:47:17
Active SMB sessions:
  MILTON-WADDAMS is connected from 192.168.25.130 for 1s, idle for [not idle]

Exploitation — Metasploit psexec

With valid credentials for milton-waddams, Brett moved to Metasploit. The screenshot insider_msconsole_24.png shows use 24 in msfconsole — module index 24 corresponds to:

exploit/windows/smb/psexec

This exploit authenticates over SMB using the compromised credentials and uploads a payload executable to the target. The console output confirms:

Selecting native target
Uploading payload... VdMXyqeN.exe

The randomly-named VdMXyqeN.exe is the Meterpreter payload dropped to the target system at 192.168.25.136:445.

Post-Exploitation — Meterpreter Session

With a Meterpreter shell established, Brett navigated the filesystem and took screenshots. The first screenshot shows Active Directory Users and Computers open — Brett was performing AD reconnaissance through the compromised CISO account.

The session commands show navigation to Milton’s desktop:

meterpreter > cd "Documents and Settings"
meterpreter > cd milton-waddams
meterpreter > cd desktop
meterpreter > upload WARNING.txt

The blackmail note WARNING.txt was uploaded to:

C:\Documents and Settings\milton-waddams\desktop

Extortion — BTC Demand

The second screenshot (insider_warning_btc_add.png) shows the WARNING.txt contents demanding 50 BTC payment to:

mpMKeox8YRCvwEVMuijgwmGnJpMJvFhL683

Note: the mp prefix identifies this as a Bitcoin testnet address — suggesting Brett may have been testing his extortion workflow rather than operating on mainnet, or was unfamiliar with the difference.

Password Cracking — John the Ripper

The artefacts include CRACKED.txt — output from John the Ripper used to crack Brett’s own password hashes (likely recovered from the domain during his AD recon):

VERYSECURE!    (Brett-Hart:1)
URE!           (Brett-Hart:2)

The split output across two hash types reveals Brett’s full password: VERYSECURE! — ironic given the investigation.


IOCs

Type Value
IP 192.168.25.136 (target DC)
IP 192.168.25.130 (attacker)
Domain initech.local
Hostname voenmeh-d0f286a.initech.local
MAC 00:50:56:F4:3C:76
Payload VdMXyqeN.exe
BTC Address mpMKeox8YRCvwEVMuijgwmGnJpMJvFhL683
Credential milton-waddams:password
Credential it:football
Credential Brett-Hart:VERYSECURE!

MITRE ATT&CK

Technique ID Description
Network Service Discovery T1046 Nmap -sS scan of 192.168.25.0/24
Brute Force: Password Guessing T1110.001 smb-brute NSE script against all accounts
SMB/Windows Admin Shares T1021.002 psexec exploit over SMB port 445
Ingress Tool Transfer T1105 VdMXyqeN.exe payload uploaded via psexec
Screen Capture T1113 Meterpreter screenshot of AD Users and Computers
Data Encrypted for Impact / Extortion T1486 WARNING.txt uploaded demanding 50 BTC
Password Cracking T1110.002 John the Ripper used to crack NTLM hashes

Defender Takeaways

Milton’s environment had several critical failures despite being declared “unhackable”:

Weak credentialspassword as the CISO’s password and football for a service account are trivially guessable and would fall to any wordlist attack. Password complexity enforcement and lockout policies would have blocked the smb-brute attack entirely.

SMB exposure — Port 445 was reachable from the contractor’s machine with no network segmentation. Contractors should operate in a separate VLAN with no direct access to the domain controller.

psexec allowed — Legitimate psexec use cases are narrow. Blocking or alerting on psexec-style lateral movement (Service Control Manager abuse) is a straightforward detection opportunity.

No MFA — A second factor on domain accounts would have rendered the brute-forced credentials useless for remote access even if the passwords were weak.


Q1) What time was the nmap scan initiated? (Format: XXX XXX DD HH:MM:SS YYYY)
Click flag to reveal thu Apr 11 07:10:24 2024
Q2) What is the full nmap command that ran? (Format: nmap command here)
Click to reveal answer nmap -sS --script *smb*,*ldap* -sV --version-all -T5 -oN scan.txt 192.168.25.0/24
Q3) What is the MAC address of the first responding IP? (Format: xx:xx:xx:xx:xx:xx)
Click flag to reveal 00:50:56:F4:3C:76
Q4) What is the domain as determined by the LDAP scripts? (Format: string.tld)
Click to reveal answer initech.local
Q5) What is the dnsHostName? (Format: string.string.tld)
Click flag to reveal voenmeh-d0f286a.initech.local
Q6) Which enabled accounts had passwords guessed by the SMB brute force script? (Format: string, string)
Click to reveal answer it, milton-waddams
Q7) What is the IP of the connecting machine in the active SMB session, and when did they log in? (Format: xx.xx.xx.xx, YYYY-MM-DDTHH:MM:SS)
Click flag to reveal 192.168.25.130, 2024-04-11T10:47:17
Q8) What exploit did the attacker use in msfconsole? (Format: something/something/something/something)
Click to reveal answer exploit/windows/smb/mpsexec
Q9) What was the name of the uploaded payload? (Format: name.extension)
Click flag to reveal VdMXyqeN.exe
Q10) What is the title of the open Window in the first grabbed screenshot? (Format: Window Name)
Click to reveal answer active directory users and computers
Q11) What file did the attacker upload and where? (Format: name.extension, c:\path\to\folder)
Click flag to reveal warning.txt c:\Documents and Setting\milton-addams\desktop
Q12) What is the BTC address in the second grabbed screenshot? (Format: address)
Click to reveal answer mpMKeox8YRCvwEVMuijgwmGnJpMJvFhL683
Q13) What tool is CRACKED.txt the output of? (Format: tool)
Click flag to reveal john
Q14) What is the password for Brett? (Format: password)
Click to reveal answer VERYSECURE!
🔒
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