In the context of CompTIA CySA+ and vulnerability management, the distinction between credentialed and non-credentialed scanning is defined by the level of access the scanner is granted to the target system during the assessment.
Non-credentialed scanning (unauthenticated) simulates the perspectiv…In the context of CompTIA CySA+ and vulnerability management, the distinction between credentialed and non-credentialed scanning is defined by the level of access the scanner is granted to the target system during the assessment.
Non-credentialed scanning (unauthenticated) simulates the perspective of an external attacker or an outsider without login privileges. The scanner interacts with the target only over the network, identifying open ports, active services, and responding protocols. It relies on techniques like banner grabbing and TCP/IP fingerprinting to estimate operating system details and potential vulnerabilities. While effective for mapping the network perimeter and validating firewall rules, it lacks visibility into the host's internal state. This approach often results in a higher rate of false positives and misses client-side vulnerabilities (such as outdated web browsers) or internal misconfigurations.
Credentialed scanning (authenticated) involves providing the scanner with valid administrative credentials (username/password or SSH keys). This allows the tool to log into the target system and query the device from the inside. By accessing the file system, registry, and package managers, credentialed scans can accurately identify missing security patches, weak password policies, malware artifacts, and software vulnerabilities not exposed through network ports.
For a cybersecurity analyst, credentialed scans are essential for a comprehensive and accurate audit of an organization's risk posture, whereas non-credentialed scans are primarily used to assess external exposure and discover rogue devices.
Credentialed vs. Non-Credentialed Scanning
What is the Concept? In the realm of vulnerability management (a key domain of the CompTIA CySA+), scanning is generally categorized into two methodologies based on the level of access the scanner has to the target system: Credentialed (Authenticated) and Non-credentialed (Unauthenticated) scanning.
1. Non-Credentialed Scanning This method simulates the perspective of an external attacker—specifically one appearing as a 'black box' threat who has no login privileges. The scanner sends packets to the target and analyzes the responses. It relies heavily on banner grabbing and port scanning to guess the operating system and running services.
2. Credentialed Scanning This method allows the scanner to log into the target system using a privileged account (such as root or Administrator) or a dedicated service agent. Once inside, it acts as a 'white box' or insider threat. It can query the operating system directly to view the registry, file system, configuration files, and installed patch lists.
Why is it Important? Understanding the distinction is vital for accurate risk assessment. Non-credentialed scans are excellent for seeing what is exposed to the public internet (firewall testing), but they are prone to high rates of false positives (marking a vulnerability that doesn't exist) and false negatives (missing a vulnerability that is actually there). Credentialed scans provide the 'ground truth' accuracy required for rigorous compliance and patch management validation.
How it Works Non-Credentialed: The scanner probes port 80. The server responds with an HTTP header saying 'Apache 2.4.49'. The scanner checks its database and reports a vulnerability associated with that version. However, the scanner does not know if the administrator has applied a 'backported' patch that fixes the issue without changing the version number. Validating this requires manual intervention. Credentialed: The scanner logs in via SSH or SMB. It executes a command like rpm -qa or checks the Windows Registry key for installed updates. It sees exactly which KB (Knowledge Base) patches are installed. It ignores the banner and confirms the system is secure based on the actual file versions present.
Exam Tips: Answering Questions on Credentialed vs. Non-credentialed scanning For the CySA+ exam, look for specific keywords in the scenario to choose the right answer:
Choose 'Credentialed/Authenticated' if the scenario mentions: - The need to reduce False Positives. - A requirement to verify patch levels or checking registry/configuration settings. - The need for the most accurate results. - Identifying client-side software vulnerabilities (e.g., an outdated PDF reader that isn't listening on a port).
Choose 'Non-Credentialed/Unauthenticated' if the scenario mentions: - Simulating an external attacker or outsider threat. - Testing firewall rules or perimeter security visibility. - A constraint where no administrative accounts are available. - 'Banner grabbing' or 'fingerprinting' (these are the primary mechanisms used here).
Summary Tip: If the question complains that a report is too long and full of errors (noise), the solution is almost always to switch from non-credentialed to credentialed scanning.