Legit CAS-005 Exam Download

The SIEM report shows that some devices, such as VM003 (Critical server) and NET003 (IPS), are DOWN and therefore not reporting logs. In security monitoring, the absence of log data from critical systems creates dangerous blind spots. If logs are missing, attacks can proceed undetected, or investigations may lack the data needed for incident response.

The most effective action is to perform a non-reporting device assessment (C). This means identifying and correcting issues where devices fail to send logs, whether due to outages, misconfigurations, or integration gaps. Ensuring all critical devices, especially servers and intrusion prevention systems, consistently send logs to the SIEM strengthens overall visibility and monitoring posture.

Option A (time calibration) is important for correlation accuracy but does not address missing log feeds. Option B (centralized use case library) enhances detection but only works if the SIEM is receiving complete data. Option D (resiliency plan) helps protect log retention but is irrelevant if logs are never received in the first place.

Therefore, fixing non-reporting log sources is the highest priority to improve monitoring effectiveness.

To meet the requirements of having allendpoints establish telemetry with a SIEM, integrate into an XDR platform, and allow SOC services to monitor the XDR platform, the best approach is to implement Host Intrusion Prevention Systems (HIPS) and a host-based firewall. HIPS can provide detailed telemetry data to the SIEM and can be integrated into the XDR platform for comprehensive monitoring and response. The host-based firewall ensures that only authorized traffic is allowed, providing an additional layer of security.

Analysis and Remediation Options for Each IoC:

IoC 1:

Evidence:

Source: Apache_httpd

Type: DNSQ

Dest: @10.1.1.1:53,@10.1.2.5

Data: update.s.domain, CNAME 3a129sk219r9slmfkzzz000.s.domain, 108.158.253.253

Analysis:

Analysis: The service is attempting to resolve a malicious domain.

Reason: The DNS queries and the nature of the CNAME resolution indicate that the service is trying to resolve potentially harmful domains, which is a common tactic used by malware to connect to command-and-control servers.

Remediation:

Remediation: Implement a blocklist for known malicious ports.

Reason: Blocking known malicious domains at the DNS level prevents the resolution of harmful domains, thereby protecting the network from potential connections to malicious servers.

IoC 2:

Evidence:

Src: 10.0.5.5

Dst: 10.1.2.1, 10.1.2.2, 10.1.2.3, 10.1.2.4, 10.1.2.5

Proto: IP_ICMP

Data: ECHO

Action: Drop

Analysis:

Analysis: Someone is footprinting a network subnet.

Reason: The repeated ICMP ECHO requests to different addresses within a subnet indicate that someone is scanning the network to discover active hosts, a common reconnaissance technique used by attackers.

Remediation:

Remediation: Block ping requests across the WAN interface.

Reason: Blocking ICMP ECHO requests on the WAN interface can prevent attackers from using ping sweeps to gather information about the network topology and active devices.

IoC 3:

Evidence:

Proxylog:

GET /announce?info_hash=%01dff%27f%21%10%c5%wp%4e%1d%6f%63%3c%49%6d & peer_id%3dxJFS

Uploaded=0 & downloaded=0 & left=3767869 & compact=1 & ip=10.5.1.26 & event=started

User-Agent: RAZA 2.1.0.0

Host: localhost

Connection: Keep-Alive

HTTP200 OK

Analysis:

Analysis: An employee is using P2P services to download files.

Reason: The HTTP GET request with parameters related to a BitTorrent client indicates that the employee is using peer-to-peer (P2P) services, which can lead to unauthorized data transfer and potential security risks.

Remediation:

Remediation: Enforce endpoint controls on third-party software installations.

Reason: By enforcing strict endpoint controls, you can prevent the installation and use of unauthorized software, such as P2P clients, thereby mitigating the risk of data leaks and other security threats associated with such applications.

The beststrategy for securely managing cryptographic material is to use a Hardware Security Module (HSM). Here’s why:

Security and Integrity: HSMs are specialized hardware devices designed to protect and manage digital keys. They provide high levels of physical and logical security, ensuring that cryptographic material is well protected against tampering and unauthorized access.

Centralized Key Management: Using HSMs allows for centralized management of cryptographic keys, reducing the risks associated with decentralized and potentially insecure key storage practices, such as on personal laptops.

Compliance and Best Practices: HSMs comply with various industry standards and regulations (such as FIPS 140-2) for secure key management. This ensures that the organization adheres to best practices and meets compliance requirements.