CCNA Cysa Incident Response Questions

A SIEM ingests logs and alerts from disparate sources into a single platform and applies correlation rules to link related events, such as a failed login followed by a privilege escalation and outbound data transfer, into one incident timeline, directly solving the described correlation gap.

PEiD and similar packer detection tools analyze the Portable Executable (PE) headers, entry point signatures, and section characteristics to quickly and accurately identify specific packers, cryptors, or compilers. This static analysis technique is the most direct and efficient way to confirm if an executable is packed and to determine the exact packing algorithm applied.

Passive DNS databases log DNS query and response transactions captured by sensors across the internet. This allows analysts to reconstruct historical domain-to-IP mappings, identify fast-flux DNS techniques, and pinpoint when a malicious domain pointed to specific infrastructure.

Conducting a root cause analysis is the central activity of the lessons-learned phase, as it systematically identifies the underlying human, technical, or procedural factors that allowed the incident. Using structured methods like "5 Whys" or fault tree analysis, the team traces the chain of events back to initial conditions, distinguishing the immediate trigger from the deeper vulnerabilities or gaps. This analysis drives targeted remediation—such as revised hardening standards or additional training—so that similar incidents are less likely to recur.

IP addresses are fundamental network-level IOCs because they denote the source or destination of malicious traffic observed in logs, packet captures, or DNS queries. When an infection communicates with a command-and-control (C2) node or an attacker launches a brute-force attack, that IP address becomes a repeatable, searchable value in firewall logs, SIEM alerts, and threat feeds. Sharing an IP address allows other organizations to block the endpoint, but note that IPs can change quickly, making them a time-sensitive indicator.

Analyzing the Portable Executable (PE) header's import table, specifically the Import Address Table (IAT), is a fundamental static analysis technique. It explicitly lists the dynamic-link libraries (DLLs) and the specific functions that the binary requests from the operating system, such as InternetOpenA or WriteProcessMemory. This provides immediate, concrete clues about the program's intended capabilities and behavior without executing the payload.

This matches the RFC 3227 order of volatility precisely: CPU registers and cache decay in nanoseconds, RAM contents are lost on power-off within seconds, swap/pagefile persists slightly longer on disk, and log files and disk data remain until explicitly deleted, so evidence must be captured in exactly this sequence to avoid destroying the most fragile artifacts first.

Computing a cryptographic hash (e.g., SHA-256) of the original drive before imaging establishes a baseline integrity value. This baseline lets the examiner later hash the acquired image and confirm it is bit-for-bit identical to the source, proving the imaging process did not alter or omit data. Recording the hash in chain-of-custody documentation also provides legal defensibility.

Trusted Automated Exchange of Intelligence Information (TAXII) is the application-layer protocol specifically designed to route and exchange cyber threat intelligence over HTTPS. It supports multiple sharing models, such as hub-and-spoke or peer-to-peer, enabling organizations to securely automate the ingestion and dissemination of STIX-formatted data.

Directing the acquired memory image to a write-blocked destination device is a critical forensic practice that prevents accidental overwriting, modification, or contamination of the evidence. This ensures that the captured volatile data remains in an untampered state from the exact moment of acquisition through the entire chain of custody.

Rerouting traffic through a DDoS mitigation service or scrubbing center is the most effective response because these services employ specialized filtering, rate limiting, and behavioral analysis to distinguish legitimate user requests from malicious traffic, forwarding only clean traffic to the origin. This approach is well-suited for both volumetric floods and application-layer attacks, and it can be activated quickly by updating DNS or BGP to redirect traffic.

STIX provides a structured language for describing threat indicators, while TAXII defines the transport protocol for exchanging that data between platforms. MISP natively supports both, satisfying the requirement to structure and exchange threat intelligence with trusted partners. OpenIOC and PDF are unrelated formats, and Microsoft Entra ID governs identity, not intelligence sharing.

Structured Threat Information Expression (STIX) is a standardized serialization format used to model and represent structured cyber threat intelligence. Trusted Automated Exchange of Intelligence Information (TAXII) is the application-layer protocol specifically designed to securely route and exchange these STIX-formatted threat feeds over HTTPS, making them the industry standard for automated threat sharing.

LiME (Linux Memory Extractor) is a kernel-space tool designed specifically for acquiring volatile memory from Linux-based systems. It operates as a Loadable Kernel Module (LKM), allowing it to bypass user-space limitations and capture a full, uncorrupted dump of physical RAM, including volatile artifacts, while minimizing its footprint on the host system.

Implementing automated compliance checks, such as Cloud Security Posture Management (CSPM) tools, directly addresses the root cause by continuously auditing resource configurations against security baselines. These tools provide real-time detection and automated remediation of drift, ensuring that unauthorized public access is blocked immediately upon misconfiguration.

The import table lists external functions and libraries the executable calls, revealing capabilities such as network access, file manipulation, or process injection without running the code. This static inspection satisfies the no-execution constraint while exposing likely malicious behaviour.

Correct: RAM (most volatile) first, then CPU registers, then swap, then network connections, then disk, then archived media. This follows the standard order of volatility.

Volatile memory (RAM) contains transient data such as active network connections, running processes, and unencrypted cryptographic keys that are lost upon system shutdown or reboot. Utilizing a dedicated tool like WinPmem allows analysts to capture a physical memory dump immediately after securing the system. This adheres strictly to the Order of Volatility, ensuring critical, short-lived evidence is preserved before any disk-based collection occurs.

Performing a root cause analysis (RCA) is the definitive post-incident activity required to identify the underlying vulnerabilities and systemic failures that allowed the breach to succeed. By pinpointing the exact vector, security teams can implement permanent, strategic remediation controls to prevent similar incidents.

Structured Threat Information Expression (STIX) is an XML/JSON-based serialization language that standardizes the representation of cyber threat intelligence. It allows organizations to share structured data about threat actors, campaigns, indicators, and tactics in a consistent, machine-readable format.

Trusted Automated eXchange of Indicator Information (TAXII) is an application-layer protocol specifically designed to route cyber threat intelligence (CTI) over HTTPS. It supports common sharing models such as hub-and-spoke or peer-to-peer, allowing CSIRTs to automate the secure distribution and ingestion of STIX-formatted IoCs directly into security tools.

LiME (Linux Memory Extractor) is a kernel-mode tool specifically designed for volatile memory acquisition on Linux systems. It operates as a Kernel Loadable Module (LKM), allowing investigators to capture full RAM dumps with minimal footprint and high integrity, even bypassing restrictions that might block user-space memory access.

This sequence accurately represents the descending order of volatility according to RFC 3227 guidelines. CPU registers and cache are the most transient, followed by system RAM, then swap/paging files, local hard disks, and finally remote or archived logs. Following this order during an incident response ensures that the most fragile, short-lived digital evidence is preserved before it is overwritten by system processes or power loss.