Free Practice Questions for CompTIA CAS-004 Exam

The most likely cause of the signature failing is that the certificate is set for the wrong key usage. Key usage is an extension of a certificate that defines the purpose and functionality of the public key contained in the certificate. Key usage can include digital signature, key encipherment, dataencipherment, certificate signing, and others. If the certificate is set for a different key usage than digital signature, it will not be able to sign the applications properly. The administrator should check the key usage extension of the certificate and make sure it matches the intended purpose. Verified References:

https://www.wintips.org/how-to-fix-windows-cannot-verify-the-digital-signature-for-this-file-error-in-windows-8-7-vista/

https://softwaretested.com/mac/how-to-fix-a-digital-signature-error-on-windows-10/

https://support.microsoft.com/en-us/office/digital-signatures-and-certificates-8186cd15-e7ac-4a16-8597-22bd163e8e96

Rules of engagement are legal documents that should be signed by all parties involved in an assessment to ensure they understand their roles and responsibilities. Rules of engagement define the scope, objectives, methods, deliverables, limitations, and expectations of an assessment project. They also specify the legal and ethical boundaries, communication channels, escalation procedures, and reporting formats for the assessment. Rules of engagement help to avoid misunderstandings, conflicts, or liabilities during or after an assessment.

Wireless network auto joining is the mobile configuration setting that the mobile administrator is verifying by reviewing the mobile device DHCP logs. Wireless network auto joining is a feature that allows mobile devices to automatically connect to a predefined wireless network without requiring user intervention or authentication. This can be useful for corporate or trusted networks that need frequent access by mobile devices. The DHCP logs show that the mobile devices are assigned IP addresses from the wireless network with SSID “CorpWiFi”, which indicates that they are auto joining this network.

The indicator that shows when a company might not be viable after a disaster is the maximum tolerable downtime (MTD). MTD is the maximum amount of time that a business process or function can be disrupted without causing unacceptable consequences for the organization. MTD is a key metric for business continuity planning and disaster recovery, as it helps determine the recovery time objective (RTO) and the recovery point objective (RPO) for each process or function. If the actual downtime exceeds the MTD, the organization may face severe losses, reputational damage, regulatory penalties, or even bankruptcy. Verified References:

https://www.techtarget.com/searchdisasterrecovery/definition/maximum-tolerable-downtime

https://www.techtarget.com/searchdisasterrecovery/definition/recovery-time-objective

https://www.techtarget.com/searchdisasterrecovery/definition/recovery-point-objective

The analyst should implement every solution one at a time in a virtual lab, running an attack simulation each time while collecting metrics. Roll back each solution and then implement the next. Choose the best solution based on the best metrics. This approach would allow the analyst to test each solution individually and measure its effectiveness against the attack, without affecting the other solutions or the production environment. This would also minimize the downtime required to implement the best solution, as only one change would be needed. The other options would either involve implementing multiple solutions at once, which could cause conflicts or errors, or collecting metrics before running the attack simulation, which would not reflect the actual impact of the solutions.

DMARC (Domain-based Message Authentication, Reporting and Conformance) and SPF (Sender Policy Framework) are two mechanisms that can help detect and prevent email spoofing, which is the creation of email messages with a forged sender address. DMARC allows a domain owner to publish a policy that specifies how receivers should handle messages that fail authentication tests, such as SPF or DKIM (DomainKeys Identified Mail). SPF allows a domain owner to specify which mail servers are authorized to send email on behalf of their domain. By checking the DMARC and SPF records of the sender’s domain, a receiver can verify if the email is from a legitimate source or not. Verified References:

https://en.wikipedia.org/wiki/Email_spoofing

https://en.wikipedia.org/wiki/DMARC

https://en.wikipedia.org/wiki/Sender_Policy_Framework

Purchasing one wildcard certificate is the best solution to protect multiple websites hosted by an organization in a cloud-hosted WAF. A wildcard certificate is a type of SSL/TLS certificate thatcan secure a domain name and any number of its subdomains with a single certificate. For example, a wildcard certificate for *.mycompany.com can secure www.mycompany.com, campus.mycompany.com, and any other subdomain under mycompany.com. A wildcard certificate can save costs and simplify management compared to purchasing individual certificates for each website.

Delivering an updated threat signature throughout the endpoint detection and response (EDR) system is the best way to take advantage of the security solution that uses a sandbox environment to execute zero-day software and collect indicators of compromise. An EDR system is a solution that monitors and analyzes the activities and behaviors of endpoints, such as computers, mobile devices, or servers, and detects and responds to potential threats. An EDR system can use threat signatures, which are patterns or characteristics of known malicious software or attacks, to identify and block malicious activities on endpoints. By delivering an updated threat signature based on the indicators ofcompromise collected from the sandbox environment, the organization can enhance its EDR system’s ability to detect and prevent zero-day attacks that exploit unknown vulnerabilities. Verified References:

https://www.cisco.com/c/en/us/products/security/what-is-endpoint-detection-response.html

https://www.crowdstrike.com/epp-101/what-is-a-sandbox/

The company should use CASB for OAuth application permission control to help prevent this type of attack in the future. CASB stands for cloud access security broker, which is a software tool that monitors and enforces security policies for cloud applications. CASB can help control which third-party applications can access the company’s cloud file storage service and what permissions they have. CASB can also detect and block any unauthorized or malicious applications that try to access the company’s data. Verified References:

https://www.kaspersky.com/resource-center/threats/how-to-avoid-social-engineering-attacks

https://www.eccouncil.org/cybersecurity-exchange/ethical-hacking/understanding-preventing-social-engineering-attacks/

https://www.indusface.com/blog/10-ways-businesses-can-prevent-social-engineering-attacks/

Executing the files in the sandbox on the web proxy is the best solution to reduce the risk of employees downloading and opening malicious files from the internet. A sandbox is a secure and isolated environment that can run untrusted or potentially harmful code without affecting the rest of the system. By executing the files in the sandbox, the web proxy can analyze their behavior and detect any malicious activity before allowing them to reach the corporate workstations.

The company should use HMAC SHA256 as a cryptographic technique to ensure that packets received between two parties have not been tampered with and the connection remains private. HMAC stands for hash-based message authentication code, which is a method of generating a message authentication code using a cryptographic hash function and a secret key. HMAC can provide both integrity and authenticity of the packets, as well as resistance to replay attacks. SHA256 is a specific hash function that produces a 256-bit output. SHA256 is considered secure and widely used in various cryptographic applications. Verified References:

https://www.ericsson.com/en/blog/2021/7/cryptography-and-privacy-protecting-private-data

https://www.mdpi.com/journal/cryptography/special_issues/Preserve_Enhance_Privacy

https://link.springer.com/article/10.1007/s11432-021-3393-x

The EDR output shows the process tree of the ransomware infection. The root node is NO-AV.exe, which is a malicious executable that disables antivirus software and downloads the DearCry ransomware. The NO-AV.exe process was launched on cpt-ws026 by a user named John. The DearCry.exe process was then launched on cpt-ws026 by NO-AV.exe and propagated to other devices via SMB. Therefore, the ransomware originated from cpt-ws026 and NO-AV.exe. Verified References:

https://www.microsoft.com/security/blog/2021/03/12/analyzing-dearcry-ransomware-the-first-attack-to-exploit-exchange-server-vulnerabilities/

https://www.crowdstrike.com/blog/dearcry-ransomware-analysis/

SD-WAN (Software-Defined Wide Area Network) is a technology that allows organizations to use multiple, low-cost Internet connections to create a secure and dynamic WAN. SD-WAN can provide benefits such as lower costs, higher performance, and easier management compared to traditional WAN technologies, such as MPLS (Multiprotocol Label Switching).

However, SD-WAN also introduces some potential risks, such as:

The reliability and security of the Internet connections, which may vary depending on the location, provider, and traffic conditions.

The compatibility and interoperability of the SD-WAN hardware and software, which may come from different vendors or use different standards.

The availability and quality of the SD-WAN provider’s support, which may depend on the provider’s size, reputation, and outsourcing practices.

In this case, the CISO would most likely identify the risk that the SD-WAN provider uses a third party for support, because this could:

Affect the organization’s ability to resolve issues or request changes in a timely and effective manner.

Expose the organization’s network data and configuration to unauthorized or malicious parties.

Increase the complexity and uncertainty of the SD-WAN service level agreement (SLA) and contract terms.