The most secure way to prevent inadvertent data disclosure when encrypted SSDs are reused is to securely delete the encryption keys used by the SSD. Without the encryption keys, the data on the SSD remains encrypted and is effectively unreadable, rendering any residual data useless. This method is more reliable and efficient than overwriting data multiple times or using other physical destruction methods.
Reference:
CompTIA SecurityX Study Guide: Highlights the importance of managing encryption keys and securely deleting them to protect data.
NIST Special Publication 800-88, "Guidelines for Media Sanitization": Recommends cryptographic erasure as a secure method for sanitizing encrypted storage devices.

Comprehensive and Detailed
Understanding the Security Event:
Administrator accounts are highly privilegedand require strict monitoring.
Server 4 shows failed login attempts for the administrator account.This could indicate abrute-force attack or unauthorized access attempt.
The fact thatnone of the admin login attempts were successfulsuggestssomeone was trying to guess the credentials.
Why Option D isCorrect:
Failed logins for administrator accounts are a critical security concern.
If an attacker gains access, they couldescalate privileges and compromise the network.
Investigatingunauthorized admin login attemptsshould be thetop priorityin a log audit.
Why Other Options Are Incorrect:
A (Endpoint not submitting logs):While this is concerning, it does not indicate anactive attack.
B (Lateral movement):There's no evidence of a compromised account moving between servers yet.
C (Misconfigured syslog server):False negatives are a possibility, but thefailed admin loginsare real.
Reference:
CompTIA SecurityX CAS-005 Official Study Guide:SIEM & Incident Analysis MITRE ATT&CK (T1078.002):Valid Accounts - Administrator Compromise

Comprehensive and Detailed Step-by-Step
Sigma (A) is a rule-based detection language that is vendor-agnostic, meaning it can be used across different SIEM (Security Information and Event Management) tools. Unlike YARA (B), which focuses on file-based detection, Sigma provides a standardized way to create rules that work across various security platforms.

The logs reviewed for the user indicate that access is being denied due to time-based access restrictions. These restrictions are commonly implemented to limit access to systems during specific hours to enhance security. If a user attempts to authenticate outside of the allowed time window, access will be denied. This measure helps prevent unauthorized access during non-business hours, reducing the risk of security incidents.
Reference:
CompTIA SecurityX Study Guide: Covers various access control methods, including time-based restrictions, as a means of enhancing security.
NIST Special Publication 800-53, "Security and Privacy Controls for Information Systems and Organizations": Recommends the use of time-based access restrictions as part of access control policies.
"Access Control and Identity Management" by Mike Chapple and Aaron French: Discusses the implementation and benefits of time-based access restrictions.

Software Composition Analysis (SCA) is the best method for identifying all components, dependencies, and open-source libraries used in an application. It ensures that organizations track and manage vulnerabilities in third-party code before deployment.
SCA tools generate a Software Bill of Materials (SBOM), which provides a full representation of the code and modules used in the application.
Other options:
Static Application Security Testing (SAST) (C) checks for vulnerabilities but does not map dependencies.
Interactive Application Security Testing (IAST) (D) works at runtime, not before deployment.
Runtime Application Self-Protection (RASP) (B) works while the application is running.