CompTIA CAS-004 Practice Test - Questions Answers, Page 41

In the context of a private cryptographic key suspected to be exposed, the best immediate action is to revoke the certificate associated with that key. Revoking the certificate ensures that it cannot be used to establish new secure sessions, which prevents attackers from using the potentially compromised key to impersonate or decrypt communications. The revocation process typically involves updating the Certificate Revocation List (CRL) or leveraging the Online Certificate Status Protocol (OCSP), both of which are used by clients to check the validity of certificates.

Signed applications ensure the integrity of the application by verifying that the source code has not been tampered with. Digital signatures provide a cryptographic guarantee that the software is exactly as the developer released it.

The logs indicate a directory traversal attempt (/../..//.etc/shadow), which is a type of attack that exploits insufficient security validation/sanitization of user-supplied input file names, so that characters representing 'traverse to parent directory' are passed through to the file APIs. The /etc/shadow file on Unix systems contains password hashes. If an attacker successfully exploited this vulnerability, they could potentially access the hashed SSH password. This information could then be used to gain unauthorized access to the server if the hash was cracked.

Traffic mirroring, also known as port mirroring or SPAN (Switched Port Analyzer), involves creating a copy of the actual network traffic for independent analysis. This would allow the third-party vendor to review communications between infrastructure endpoints, identify unauthorized and malicious data patterns, and perform automated, risk-mitigating configuration changes without impacting the live environment. This is used in network intrusion detection systems (NIDS) and for traffic analysis purposes.

The SAN (Subject Alternative Name) field in a certificate can include multiple types of entries, including DNS names and email addresses. These are explicit options within the SAN extension, allowing a single certificate to be valid for multiple domain names and email addresses. This is often used in multi-domain SSL certificates, where a single certificate needs to be valid for multiple subdomains or different domain names.

The first step in mitigating the risk associated with delayed patching is to conduct a vulnerability analysis. This process involves identifying, categorizing, and assessing the vulnerabilities within the hospital's IT infrastructure. By understanding the specific vulnerabilities and their potential impact on patient care and data availability, the hospital can prioritize patching efforts effectively and develop a strategy that minimizes disruptions while ensuring critical systems remain secure.

Record-level encryption is primarily used to protect sensitive information stored in specific fields within a database, such as personal data, financial information, or health records. This encryption method ensures that individual data entries are encrypted, providing a high level of security and privacy by making the data unreadable to unauthorized users or in the event of a database breach, while still allowing the database to be functional for authorized queries and operations.

Air gapping, which means physically isolating a secure network from unsecured networks, including the public internet, is one of the most effective ways to prevent side-channel attacks. By creating an air gap, you remove the pathways that an attacker might exploit to gain unauthorized access to sensitive systems and manipulate them, as in the case of the SCADA system mentioned.

PowerShell is a versatile scripting language that can be used to automate administrative tasks and configurations on Windows machines. It has the capability to edit registry keys, which is what the red team appears to have done based on the provided information. PowerShell is a common tool used by both system administrators and attackers (in the form of a red team during penetration testing).