Top 10 Red Team Security Engineer Interview Questions
1. How would you approach a red team engagement from start to finish?
I approach red team engagements with a methodical process that begins with thorough reconnaissance. First, I gather intelligence about the target organization using both passive techniques like OSINT and active scanning to identify potential entry points. For example, in a recent engagement, we discovered an outdated VPN appliance through Shodan that became our initial access vector. After establishing the scope and rules of engagement with stakeholders, I develop a comprehensive attack plan with clear objectives, such as accessing specific sensitive data or systems. During execution, I employ a variety of tactics to maintain stealth, like living-off-the-land techniques and mimicking legitimate user behavior to avoid detection. For instance, we've used PowerShell Empire with custom obfuscation to evade antivirus while maintaining command and control. Documentation is critical throughout the engagement - I meticulously record each step, including timestamps, techniques used, and systems accessed. This creates an audit trail that helps the blue team understand how the attack unfolded. After achieving objectives, I conduct a thorough cleanup to remove any artifacts or backdoors. The final report includes not only technical findings but also strategic recommendations for improving security posture. I always emphasize constructive feedback rather than simply highlighting failures, focusing on how the organization can implement defense-in-depth strategies to address the vulnerabilities we exploited.
2. Describe a time when you had to bypass a modern EDR solution during a red team exercise.
During a recent engagement for a financial services client, we encountered CrowdStrike Falcon deployed across their environment. Rather than attempting to defeat the EDR directly, I focused on understanding its detection capabilities first. I set up a lab environment with the same EDR solution to test various techniques and observe what triggered alerts. Through this research, I discovered that while the EDR was effective at detecting common attack patterns, it had limitations with certain in-memory operations. I developed a custom loader that leveraged direct system calls rather than using Windows API functions, effectively bypassing the EDR's hooking mechanisms. The loader injected shellcode into a legitimate process (notepad.exe) using a technique called process hollowing, but with modifications to avoid common detection signatures. To further evade detection, I implemented sleep timers and jitter in the C2 communications, making the traffic pattern appear more natural and less suspicious. I also utilized a signed binary proxy execution technique where I used Microsoft-signed binaries to execute my malicious code, leveraging the trust placed in these legitimate executables. When moving laterally through the network, I carefully mimicked the behavior patterns of the IT administrators by operating during their normal working hours and using similar tools they would typically use. This approach allowed us to maintain persistence for over two weeks without detection, eventually reaching our target - the financial data processing systems. The client was impressed with our ability to remain undetected, which highlighted significant gaps in their detection capabilities despite having invested in premium security tools.
3. How do you stay current with the latest attack techniques and security vulnerabilities?
I maintain a multi-faceted approach to staying current with emerging threats and techniques. Daily, I follow several security researchers on Twitter who frequently share new vulnerabilities and attack methodologies - accounts like @maldevel and @_johnhammond have been particularly valuable sources. I'm an active member of several private Discord communities where security professionals share techniques that aren't widely publicized. For structured learning, I dedicate at least 5 hours weekly to platforms like HackTheBox and TryHackMe, where I can practice new exploitation techniques in safe environments. For example, I recently worked through a challenge involving Log4Shell vulnerabilities to better understand the nuances of JNDI injection attacks. I regularly read academic security papers from conferences like Black Hat and DEF CON, which often reveal cutting-edge research before it becomes widely known. To understand the defensive perspective, I follow the MITRE ATT&CK framework updates and study how blue teams are adapting their detection strategies. I've found that participating in bug bounty programs helps me apply theoretical knowledge in real-world scenarios - last month I discovered an SSRF vulnerability that could have led to AWS credential exposure in a major SaaS platform. I also contribute to open-source security tools; I recently added a module to CrackMapExec that implements a novel technique for extracting credentials from Windows credential providers. Attending virtual security conferences and workshops has been invaluable, especially smaller, more technical events like NorthSec and OffensiveCon where cutting-edge techniques are often demonstrated. Finally, I maintain a personal lab environment where I can safely test new exploits and tools before considering them for actual red team engagements.
4. What methodologies do you use for privilege escalation in Windows environments?
In Windows environments, I employ a systematic approach to privilege escalation that begins with thorough enumeration. I start by gathering basic system information using tools like PowerUp or WinPEAS to identify low-hanging fruit such as unquoted service paths or weak service permissions. For example, on a recent engagement, I discovered a service running as SYSTEM with modifiable executable paths, which allowed me to replace the legitimate executable with my payload. I always check for credential exposure in the Windows Registry, Group Policy Preference files, and configuration files - it's surprising how often credentials are stored in plaintext or using reversible encryption. Kernel exploits can be powerful, but I use them judiciously due to stability concerns; I recently leveraged the PrintNightmare vulnerability (CVE-2021-34527) to gain SYSTEM privileges on a server that hadn't been patched in several months. UAC bypass techniques are essential in my toolkit - I've successfully used the fodhelper.exe bypass to elevate from a standard user to high integrity without prompting the user. I also look for DLL hijacking opportunities by identifying applications that load DLLs from paths where I have write permissions. For lateral movement, I examine token privileges like SeImpersonatePrivilege which can be exploited using tools like Juicy Potato or PrintSpoofer. Always-installed Windows features like WSUS can be abused if misconfigured - I've exploited WSUS using the WSUXploit tool to deliver malicious updates when HTTPS wasn't enforced. In domain environments, I hunt for Kerberoasting opportunities by identifying service accounts with weak passwords, and I've successfully used Mimikatz to extract credentials from memory. I maintain detailed notes throughout this process, as privilege escalation often involves combining multiple smaller vulnerabilities to achieve the desired access level.
5. How would you approach a phishing campaign as part of a red team assessment?
When designing a phishing campaign for a red team assessment, I first conduct thorough reconnaissance to understand the target organization's culture and communication patterns. I'll review their public-facing emails, social media presence, and even job postings to identify the tone and terminology commonly used. For a healthcare organization I assessed, I noticed they frequently communicated about compliance training, which became the theme for our campaign. I then create a pretext that's both compelling and plausible - for that healthcare client, we impersonated their compliance department announcing a new HIPAA training requirement with an urgent deadline. The technical infrastructure is crucial; I set up dedicated domains that appear legitimate, often using typosquatting techniques like replacing an 'l' with an 'i' or adding a hyphen. For email delivery, I use tools like GoPhish or Evilginx while implementing proper SPF, DKIM, and DMARC configurations to increase deliverability. The landing pages are meticulously crafted to mirror legitimate sites, including proper SSL certificates and familiar branding elements. I develop multiple payload types depending on the assessment goals - from credential harvesters to macro-enabled documents that establish C2 connections. For the healthcare client, we created a fake training portal that harvested credentials and then redirected users to the actual training site so they wouldn't suspect anything. Timing is strategic; I typically send phishing emails during busy periods when people are more likely to act hastily, like Monday mornings or just before major deadlines. After execution, I analyze metrics beyond just click rates - examining how quickly users interacted with the phish, whether they reported it to security teams, and if they entered credentials or enabled macros. This comprehensive approach has consistently achieved success rates above 30% in initial access, providing valuable insights into the human element of an organization's security posture.
6. What tools and techniques do you use for lateral movement once you've gained initial access?
Lateral movement requires a blend of stealth and efficiency to avoid detection while expanding access. After gaining initial foothold, I first conduct passive internal reconnaissance using tools like BloodHound to map out the Active Directory environment and identify potential paths to high-value targets. For example, in a recent engagement, BloodHound revealed that a compromised help desk account had administrative access to several finance department workstations through nested group memberships. I heavily rely on legitimate administrative tools like PsExec, WMI, and PowerShell Remoting since these blend in with normal administrative activities. When using these tools, I'm careful to match the patterns of legitimate administrators - operating during business hours and avoiding unusual command sequences that might trigger behavioral analytics. For credential harvesting, I use a combination of Mimikatz for in-memory extraction and Rubeus for Kerberos ticket manipulation, which recently allowed me to perform a Kerberoasting attack against a service account with domain admin privileges. To maintain stealth, I implement SMB named pipes for C2 communications when moving between systems, as this traffic is often overlooked in monitoring solutions. I've found that DCOM lateral movement techniques are particularly effective in environments with strict PowerShell logging, as they can achieve code execution while generating minimal suspicious logs. When dealing with segmented networks, I leverage compromised jump hosts and port forwarding to establish pivots, using tools like Chisel or SSH tunneling depending on what's available in the environment. For persistence across multiple systems, I deploy lightweight beacons that communicate using encrypted protocols that mimic legitimate application traffic, such as HTTPS with domain fronting to trusted CDNs. Throughout the lateral movement phase, I maintain detailed documentation of access paths and credentials, which not only helps with the assessment report but also ensures I can properly clean up after the engagement concludes.
7. How do you evade detection during a red team operation?
Evading detection requires understanding both technical controls and human analyst behavior. I start by researching the target's security stack through open source intelligence - job postings often reveal which SIEM, EDR, and other security tools an organization uses. For a recent engagement where I knew the client used Microsoft Defender ATP, I developed custom obfuscation techniques for my PowerShell scripts that broke known detection signatures while maintaining functionality. I'm meticulous about operational security, using dedicated infrastructure for each engagement and implementing proper segmentation to prevent attribution. When deploying payloads, I use staged delivery methods where the initial payload is minimal and appears benign, only retrieving the actual malicious code after performing environmental checks to confirm it's not running in a sandbox. I've found that timing operations to coincide with periods of expected network activity helps mask C2 traffic - for instance, scheduling large data exfiltration during backup windows when high data transfer is normal. For command and control, I implement jitter in my callbacks (varying the timing between 15-45 minutes) and use legitimate web services like Microsoft Teams webhooks as communication channels, which blend perfectly with normal business traffic. I carefully study the target's logging infrastructure and modify my techniques to generate minimal or ambiguous logs - for example, using direct system calls instead of API functions that are commonly hooked by security products. When moving files across the network, I use alternate data streams or embed data in seemingly benign files like images using steganography techniques. I also implement "living off the land" techniques extensively, leveraging built-in Windows utilities like certutil.exe for file transfers or scheduled tasks for persistence rather than dropping custom tools. Throughout the engagement, I maintain a low and slow approach, limiting the number of actions taken within specific timeframes to avoid triggering frequency-based alerts that might flag unusual activity patterns from a single source.
8. Describe how you would conduct a physical security assessment as part of a red team engagement.
Physical security assessments begin with thorough reconnaissance of the target facility. I typically start by examining publicly available information like Google Maps satellite imagery, social media posts from employees, and any available floor plans or evacuation maps. For a manufacturing client, I discovered detailed facility layouts in publicly filed permit applications that provided invaluable insights into their security measures. Before attempting any entry, I conduct multiple drive-bys and observations at different times to identify patterns - when employees take smoke breaks, when cleaning crews arrive, or when shift changes occur. These observations help identify optimal timing for attempted access. I prepare multiple pretexts and corresponding props based on the organization's culture - for a tech company, I've successfully posed as an IT contractor with a convincing work order and appropriate tools. Tailgating remains one of the most effective techniques; I've found that carrying a box or several cups of coffee often prompts employees to hold doors open without questioning. For bypassing electronic access controls, I use techniques like relay attacks against proximity cards or exploiting vulnerabilities in older access control systems. During one assessment, I used a modified long-range RFID reader to capture card data from employees as they entered the building, which I later cloned to gain access. Once inside, I document security weaknesses through discreet photography and notes, focusing on sensitive areas like server rooms, executive offices, or R&D labs. I look for exposed sensitive information (passwords on sticky notes, unlocked computers), inadequate camera coverage, and improper storage of sensitive materials. I also test the security awareness of employees by attempting to access restricted areas or asking for assistance that violates security policies. Throughout the assessment, I maintain a professional demeanor and carry authorization documentation in case I'm challenged by security personnel. The final report includes a detailed timeline of my activities, what security controls were effective, which ones failed, and specific recommendations for improvement based on observed vulnerabilities.
9. How do you approach writing a comprehensive red team report that provides actionable insights?
A comprehensive red team report must balance technical detail with strategic insights that executives can understand and act upon. I structure my reports to tell the complete story of the engagement, beginning with an executive summary that clearly articulates the scope, objectives, and key findings without technical jargon. For a financial services client, I used a risk-based approach in the summary, highlighting how our successful compromise of their payment processing system could have resulted in regulatory violations and financial losses. The methodology section details my approach chronologically, explaining the tactics, techniques, and procedures (TTPs) used at each stage of the attack chain. I map these to the MITRE ATT&CK framework to provide context and help the blue team understand the attack patterns. For technical findings, I include detailed evidence including screenshots, command outputs, and logs that demonstrate the exploitation process. Each finding includes a clear description of the vulnerability, the exploitation method used, potential business impact, and specific remediation steps. For example, when documenting an SQL injection vulnerability that led to customer data access, I included the exact injection string used, database schema exposed, and code snippets showing proper input validation techniques. I prioritize findings based on a combination of exploitation difficulty and potential business impact rather than using generic CVSS scores alone. The report includes a detailed attack timeline that helps security teams understand how long certain activities went undetected and where their detection gaps exist. I always include a section on what worked well - security controls that were effective or detections that occurred - to provide positive reinforcement and a complete picture of the security posture. For remediation, I provide both tactical quick wins and strategic recommendations with implementation timelines based on risk. I conclude with appendices containing all technical details that would be valuable for security engineers implementing fixes, including IOCs, hashes of tools used, and IP addresses of attack infrastructure to help with threat hunting exercises after the engagement concludes.
10. How would you test the effectiveness of a company's security awareness program during a red team engagement?
Testing security awareness requires a multi-faceted approach that evaluates both technical controls and human behavior. I design scenarios that target different aspects of security awareness, starting with phishing campaigns that vary in sophistication. For a retail client, I created three tiers of phishing emails: obvious attempts with spelling errors, moderate attempts mimicking common services like Office 365, and sophisticated spear-phishing targeting executives with highly personalized content. This approach helps identify which employee groups might need additional training. I also test physical security awareness by attempting tailgating into secure areas or leaving USB drives in common areas to see if employees plug unknown devices into corporate systems. During one engagement, I left branded USB drives labeled "Confidential: Salary Information 2024" in the break room, which were plugged in by 7 out of 10 employees who found them. I evaluate phone-based social engineering (vishing) by calling employees with various pretexts, such as impersonating IT support requesting credentials for "system updates" or claiming to be new employees needing assistance accessing systems. The response patterns reveal how well security policies have been internalized across different departments. I assess how employees handle sensitive information by requesting access to systems or data through improper channels, noting whether they follow verification procedures or grant access based solely on perceived authority. Throughout these tests, I document not only successful compromises but also positive security behaviors - employees who report suspicious activities, verify identities through proper channels, or refuse to circumvent security policies despite pressure. I measure the time between compromise and reporting to gauge the effectiveness of incident response awareness. The final report includes metrics like click rates on phishing emails, reporting rates of security incidents, and compliance with security policies across different departments and seniority levels. I provide specific recommendations for improving the awareness program based on observed behaviors, such as targeted training for departments with higher susceptibility or recognition programs for employees who demonstrated exemplary security awareness during the engagement.