CPENT Practice Test 7 — 10 Questions

Question 1

An auditor finds an Amazon S3 bucket configured with public read access enabled via an Access Control List (ACL), but the bucket policy explicitly denies public read access. How does AWS evaluate these conflicting permissions?

Choose an answer to begin — your selection is scored in the full session.

Accepted Answer

The explicit Deny in the bucket policy takes precedence, resulting in access being denied.. AWS evaluates all applicable policies (identity-based, resource-based, ACLs, SCPs, permission boundaries) together, and any explicit Deny anywhere in the evaluation chain overrides every Allow. Because the bucket policy contains an explicit Deny for public read, that Deny wins over the ACL's public-read grant, and the request is denied. This is the fundamental 'explicit deny always wins' rule in AWS IAM policy evaluation logic.

Answer

AWS generates a configuration error and blocks all traffic until the conflict is resolved manually.

Answer

Access is granted because any Allow permission supersedes bucket restrictions.

Answer

The public ACL takes precedence because ACLs are evaluated before bucket policies.

Question 2

An auditor reviews an enterprise's hybrid cloud identity architecture. Which TWO of the following configurations represent insecure identity practices? (Choose TWO)

Accepted Answer

Disabling multi-factor authentication requirements for global administrator accounts during emergency maintenance windows.. Option A is correct because disabling multi-factor authentication for global administrator accounts—even temporarily during emergency maintenance—removes the strongest protection on the most privileged identities, exposing the tenant to credential-stuffing, phishing, and token-replay attacks that MFA would otherwise block. Option D is correct because non-expiring service account passwords combined with interactive logon rights create long-lived, human-usable credentials that violate least privilege and the separation of service and interactive accounts, making lateral movement and credential theft far easier. Option B is not an insecure practice: strong password complexity and expiration policies are standard hardening controls for cloud user accounts. Option C is not insecure: Microsoft Entra ID Protection is a defensive tool that detects compromised credentials and risky sign-ins. Option E is not insecure: Azure managed identities eliminate hardcoded credentials by issuing tokens through the platform, which is a recommended secure practice.

Answer

Enforcing strong password complexity and expiration policies for all cloud user accounts.

Answer

Implementing Microsoft Entra ID Protection to detect compromised credentials and risky sign-ins.

Answer

Utilizing Azure AD managed identities for Azure resources instead of hardcoded credentials.

Question 3

An OT security engineer is conducting a vulnerability assessment on a Distributed Control System (DCS). The engineer needs to test for unauthorized firmware write capabilities on a legacy controller using the Modbus protocol. Which Modbus function code is typically associated with writing multiple holding registers, which could be abused to modify configuration parameters?

Accepted Answer

Function Code 16 (0x10) - Write Multiple Registers. Modbus function codes define the action to be performed. Function Code 16 (0x10) is 'Write Multiple Registers', frequently used to change register blocks in industrial controllers.

Answer

Function Code 01 (0x01) - Read Coils

Answer

Function Code 04 (0x04) - Read Input Registers

Answer

Function Code 02 (0x02) - Read Discrete Inputs

Question 4

A penetration tester is assessing a Microsoft 365 tenant and discovers that a global administrator account has no multi-factor authentication (MFA) enforcement. The tester wants to exploit this to gain persistent access to the tenant's email and files. Which Azure AD feature, if misconfigured, would allow the attacker to maintain access even after the initial password is changed?

Accepted Answer

Azure AD application with a client secret that has a long expiration. A global administrator can create or modify an Microsoft Entra ID application and add a client secret. This secret acts as a credential for the service principal and remains valid until it expires or is revoked, regardless of the user's password changes. Attackers often use this technique to maintain persistence in Microsoft 365 environments, as it allows continued access to mail, files, and other resources granted to the application.

Answer

Azure AD password protection with a custom banned password list

Answer

Azure AD Privileged Identity Management (PIM) with just-in-time access

Answer

Azure AD Conditional Access policy that blocks legacy authentication

Question 5

A penetration tester is performing network reconnaissance against a hardened target and needs to discover live hosts while avoiding ping probes. Which Nmap option tells Nmap not to perform host discovery before scanning ports, ensuring every target IP is fully port-scanned?

Accepted Answer

-Pn. The -Pn option disables host discovery, forcing Nmap to proceed with port scanning every specified IP address as if it were online.

Answer

-R

Answer

-p-

Answer

-n

Question 6

A CPENT tester is assessing a water treatment plant's OT network. The tester has captured traffic on the plant's control VLAN and wants to enumerate all Modbus/TCP devices and their supported function codes without disrupting operations. Which Nmap NSE script should the tester run against the subnet to perform this discovery safely?

Accepted Answer

nmap -p 502 --script modbus-discover <subnet>. Modbus/TCP devices listen on TCP port 502, and the modbus-discover NSE script performs read-only device identification and function-code enumeration by sending safe Read Device Identification requests. Running a standard TCP scan against port 502 with this script enumerates PLCs without issuing writes, which meets the requirement to discover devices without disrupting plant operations.

Answer

nmap -sU -p 502 --script modbus-discover <subnet>

Answer

nmap -p 502 --script modbus-write <subnet>

Answer

nmap -p 502 --script modbus-discover --script-args modbus-discover.force=true <subnet>

Question 7

A CPENT tester gains access to an engineering workstation on an OT network and finds a project file for a Siemens SIMATIC S7-1200 PLC. The tester wants to extract the PLC's configuration, including any stored password hashes, from the engineering workstation's project data to demonstrate credential exposure. Which artifact should the tester examine?

Accepted Answer

The .ap17 project archive's SystemBlock and hardware configuration XML files, which contain PLC protection level settings and hashed password material. TIA Portal project archives (.ap17) bundle the hardware configuration and SystemBlock data as XML and binary files. These contain the PLC protection level and the hashed password used for access control. Extracting and cracking that hash from the engineering workstation demonstrates credential exposure without interacting with the live PLC, which is the goal of this assessment.

Answer

The S7-1200's web server index page, which serves the PLC password in cleartext over HTTP for diagnostic purposes

Answer

The STEP 7 project's GlobalLabels CSV export, which stores the PLC password in a readable column

Answer

The S7-1200's SD card root directory file named PASSWD.TXT, which TIA Portal writes during commissioning

Question 8

During a CPENT engagement, you have obtained a low-privileged shell on a Windows Server 2019 host that is a member of an Active Directory domain. You notice the host has the SMB signing requirement disabled. You want to perform lateral movement to other hosts on the network by capturing and relaying authentication attempts. Which tool and technique would best allow you to relay NTLM authentication to a target host where SMB signing is not enforced?

Accepted Answer

Use ntlmrelayx.py from Impacket to relay captured NTLM authentication to the target host's SMB service.. Relaying NTLM authentication is a powerful lateral movement technique when SMB signing is not enforced. The tool ntlmrelayx.py from Impacket is specifically built to relay authentication to SMB and other protocols. With SMB signing disabled on the target, the relayed authentication is accepted, allowing the attacker to execute commands or dump SAM hashes. This avoids the need to crack captured hashes and directly leverages the authentication attempt.

Answer

Use Responder with the -w flag to capture NTLMv2 hashes and then crack them offline with Hashcat.

Answer

Use Metasploit's psexec module with the current user's credentials to move laterally.

Answer

Use Mimikatz to extract plaintext credentials from memory and then use them for lateral movement.

Question 9

During an OT assessment, you capture network traffic on the plant floor and notice that a Siemens S7-1200 PLC responds to read/write requests on TCP port 102 without requiring any authentication. You want to interact with the PLC to read its current process values and verify whether an attacker could manipulate the logic. Which tool is specifically designed to communicate with Siemens S7 PLCs over the S7comm protocol for this purpose?

Accepted Answer

Snap7. Siemens S7 PLCs use the proprietary S7comm protocol over TCP port 102. To actively read/write process values or modify logic, a tool that implements S7comm is required. Snap7 is an open-source library and set of tools that provides this capability, allowing direct interaction with S7-1200, S7-1500, S7-300, and S7-400 PLCs. Other options either target different protocols or are passive/information-gathering tools.

Answer

Wireshark with the s7comm dissector

Answer

Modbus Poll

Answer

Nmap with the s7-info script

Question 10

A penetration tester has obtained domain administrator credentials for a Windows Active Directory environment. The tester wants to extract the KRBTGT account password hash to create Golden Tickets. Which method is most direct for obtaining this hash?

Accepted Answer

Run Mimikatz with the lsadump::dcsync command targeting the krbtgt account.. DCSync is a technique that impersonates a domain controller to request replication of account data, including password hashes. With domain administrator rights, Mimikatz's lsadump::dcsync can retrieve the KRBTGT hash directly from a domain controller without needing to access the DC's file system. This is the most direct and stealthy method for obtaining the KRBTGT hash to forge Golden Tickets.

Answer

Perform a Kerberoasting attack against the KRBTGT service account.

Answer

Use Volume Shadow Copy to copy the NTDS.dit file and extract hashes offline.

Answer

Run Mimikatz with the sekurlsa::logonpasswords command on a domain-joined workstation.