First off, a heartfelt thank you to Hacker Hermanos for giving me the opportunity to share my thoughts with all of you.
This article kicks off a three-part series on the art of crafting effective pretexts in social engineering engagements.
Before we dive in, let’s be crystal clear: the strategies and techniques we'll be covering are for research and professional purposes only, and should only be used when you have legal authorization to do so.
Enjoy the read—and make sure to get home before the streetlights come on!
Jeff Tomkiewicz
The GhostFace Killer
Part 1: The Foundations of Effective Pretexting
Definition and Evolution in Offensive Security
Pretexting is one of the most essential techniques in social engineering. Pretexting involves an attacker creating a fake story or taking on an identity to trick a target into revealing sensitive information or allowing unauthorized access.
For pretexting to work, the attacker has to create and maintain a believable story that fits the target's expectations, beliefs, and environment.
This tactic isn't new; it has deep roots in history. Spies from ancient times used disguises or fake stories to sneak into enemy camps, gather intel, or sabotage operations. In those cases, interactions happened face-to-face, where the attacker would pretend to be a trusted official, colleague, or service provider. The success of these early methods relied heavily on the attacker's ability to blend into the environment, understand social norms, and communicate convincingly. Psychological skills and an understanding of human behavior played key roles.
As science, technology, and communication have advanced, we've adapted these age-old techniques to the modern world.
Today, pretexting has moved beyond face-to-face interactions and expanded into digital and telecommunication spaces. It’s scalable now, allowing attackers to target multiple individuals or organizations at once. Borrowing insights from marketing and behavioral science, pretexting has become a powerful tool in Red Team engagements, helping test the defenses of complex organizations.
Pretexting has transformed from a simple, localized tactic into a sophisticated component of modern offensive security. This shift reflects broader changes in how we communicate and interact today. Modern pretexting requires more than just creating a false narrative—it's about crafting an entire experience that leverages trust, authority, and psychological principles. As technology continues to evolve, so will pretexting tactics.
Ethical Considerations and Red Team Protocols
While pretexting has been used for many purposes throughout history, today, as professionals, we have a responsibility to approach it ethically. Pretexting is a powerful tool and needs to be used carefully, especially considering these concerns:
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Trust and Deception: Pretexting inherently involves lying, which can create ethical conflicts.
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Emotional and Psychological Impact: Pretexting can play on people's fears and anxieties, especially when impersonating authority figures in the company or potentially delivering bad news (Ex: HR cutting some company perks).
- IMPORTANT: NEVER impersonate law enforcement or any civil servant authority figure. This can get you into serious legal trouble, even if the client gives you permission.
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Consent and Awareness: In some Red Team engagements, not all employees are aware that a security test is happening. This is done to make the scenario more realistic.
Because of these concerns, it's essential to stay within ethical and legal boundaries:
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Legal Compliance: Always ensure that pretexting activities are within the law. Avoid actions that could be seen as fraud, identity theft, or illegal impersonation.
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Client Agreement: Red Team activities, including pretexting, should be explicitly authorized by the client in a legally binding agreement.
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Protection of Personal Data: Any personal data collected during pretexting must be handled securely, and data protection laws must be followed.
How to Stay Ethical in Pretexting:
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Client Consent and Scope Definition: Clearly define the scope of the engagement, including the types of pretexts you will use, and ensure everything is documented and agreed upon. Informed consent is key. While not everyone in the organization might be aware of the test, senior leadership (such as the Chief Information Security Officer) should be.
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Minimizing Harm: Use pretexts that are non-distressing and avoid causing significant emotional or psychological harm. Be sure to offer debriefings and support after the operation to clear up any confusion.
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Data Protection and Confidentiality: Handle any collected data with care—use encryption and limit access. When reporting to clients, anonymize sensitive information to protect privacy.
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Ongoing Training: Red Team members should receive regular training in ethics and legal compliance to make sure they understand the full implications of their actions and can make ethical decisions in the field.
Pretexting is powerful, but it’s ethically complex. By following strict guidelines, securing client consent, minimizing harm, and protecting data, Red Teams can effectively conduct operations while maintaining a commitment to ethical conduct.
Core Elements of Pretexting
Now, let’s explore the core elements that form the foundation of believable and effective pretexts in social engineering:
Deep Research and Intelligence Gathering
When building a pretext, there are three critical elements:
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Foundation of Credibility: Success hinges on how believable your pretext is. The more authentic you appear, the more likely the target will engage with you—whether it’s clicking a link or resetting an MFA device to your control. This is where deep research and intelligence gathering are essential.
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Minimize Red Flags: Detailed research helps you avoid common mistakes that might expose your pretext, like failing to understand company jargon or misrepresenting key details.
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Tailored Approach: Every pretext should be customized based on the intelligence gathered. Intelligence drives operations, and the same applies when creating a pretext.
There are two main methods for gathering intelligence:
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Human Intelligence (HUMINT): Information gathered from human sources, like social engineering calls, networking events, or insider interviews.
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Open Source Intelligence (OSINT): Information collected from public sources, like social media, company websites, or press releases. After analyzing this data, you can decide how to act on it.
By combining OSINT and HUMINT, social engineers can build highly credible and tailored pretexts. The focus should always be on developing strong research and analytical skills rather than relying solely on tools.
Building Complex and Layered Personas
Creating a believable persona is key to successful social engineering. If your persona feels authentic, people are more likely to trust you.
Start by defining your goal:
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What is the purpose of the persona? Is it to gain access to a building or extract sensitive information?
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Who is the target audience? Knowing who the persona will interact with is crucial to shaping it.
Once the objective is clear, gather intelligence using HUMINT and OSINT. Look for opportunities where your persona can fit into the target environment. Next, build a backstory:
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Personal History: Develop a plausible backstory for your persona that fits with the target’s expectations.
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Professional Credentials: Ensure your persona’s credentials align with their role in the pretext.
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Current Context: Explain why the persona is reaching out now.
Next, develop a communication style that reflects the target's industry norms. Finally, test and refine the persona to ensure it’s consistent and believable.
Crafting Realistic Scenarios with Supporting Evidence
To make a pretext truly effective, you need to create a realistic scenario with supporting evidence. Here’s how:
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Start with an End Goal: Define the outcome you want while keeping the target’s roles and behaviors in mind.
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Incorporate Realistic Context: Use current events and organizational culture to shape your pretext.
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Create a Plausible Storyline: Keep it simple but include emotional hooks to prompt a response.
Support the pretext with "props," such as spoofed emails or fake documents, to add authenticity.
By paying attention to detail and constructing well-thought-out scenarios, social engineers can create pretexts that lead to the desired outcome while minimizing detection risks.
This concludes Part one of this three-part series. Tune in next month as we dive into case studies on effective pretexting and learn how to practice creating your own pretexts. See you then!