Publications

• June 29, 2026

  Our first observation of an AI-assisted malicious group targeting small and medium-sized Brazilian fintech companies

  Case Study

  An investigation by LESIS has identified a malicious campaign targeting small and medium-sized Brazilian fintech companies, using AI to accelerate the development of offensive tools, adapt payloads and support the exp...

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• June 25, 2026

  Dependabot: automating dependency updates on GitHub

  Guides

  Understand how Dependabot automates vulnerability monitoring and dependency updates directly on GitHub.

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• May 5, 2026

  Choosing the right method for sharing identifiers

  Case Study

  How to choose between encryption, hashes, HMAC, APIs, and PSI when comparing datasets with personal identifiers.

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• May 4, 2026

  Orientations for PII obfuscation and masking

  Guides

  Practical recommendations for masking common types of personally identifiable information without exposing useful fragments across systems.

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• April 26, 2026

  Primitives and vulnerabilities

  Research

  How thinking in primitives helps turn discrepancies between intent and real behavior into impact analysis.

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• April 26, 2026

  Digital safety for children: preparing the next generation

  Community

  Information security needs to reach people earlier. For a long time, this subject was treated as something restricted to professionals, companies, and technical teams. But reality has changed: children grow up connect...

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• April 9, 2026

  State machine for vulnerability management

  Research

  In many organizations, the vulnerability management process suffers from a recurring — yet frequently overlooked — problem: inconsistency in the definition and use of statuses. It is common to see the same statuses us...

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• February 8, 2026

  Economic taxonomy of vulnerabilities

  Research

  In cybersecurity, one of the most relevant questions and, at the same time, one of the hardest to answer precisely is: what is the financial cost of a vulnerability? Although there are several programs and practices f...

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• January 15, 2026

  Considerations for writing security reports

  Guides

  After days or weeks of work, you have identified relevant security issues, gained a solid understanding of the assessed environment’s attack surface, and gathered sufficient evidence to demonstrate real business risks...

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• January 14, 2026

  Strengthening the Brazilian cybersecurity community through education

  Community

  In 2026, LESIS will take another concrete step in its commitment to the sustainable development of the technology and information security ecosystem in Brazil. We will make a financial donation to the NGO Mente Binári...

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• November 30, 2025

  Why we sponsor information security events

  Community

  The year 2025 has been a milestone for LESIS. Between projects, research, and the growth of our presence in the market, we have also taken on a commitment we consider essential: to directly contribute to and with the ...

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• October 4, 2025

  Money for nothing, discounts for free: rocking the gift card loop

  Vulnerability

  From time to time, the opportunity arises to conduct vulnerability research on e-commerce platforms. Although the context is similar, each opportunity is unique, as there are always peculiarities in every application....

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