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Code Signature Bypass

4h 20mIntermediateJavaC#JavaScriptPythonGoTypeScript

Google has fixed a critical vulnerability in Android where an adversary could tamper with an Android app without breaking its code signature. This security bug is not specific to Android; it represents a significant design flaw present in various other languages and frameworks. Let's examine the issue and explore how to prevent this security bug in our program.

Topics

  1. Introduction

    Video15m

    There exists a vulnerability where an adversary could modify an Android app without breaking its code signature, due to a discrepancy between Java and C implementations in verifying and loading files. Let's explore this vulnerability and it's underlying issue.

  2. HTTP Parameter Pollution

    Lab40m

    Let’s head to the lab to discover, debug, and fix this vulnerability within an actual application.

  3. Lessons learnt

    Lesson5m

    Parser Differential can result in security vulnerabilities like HTTP Parameter Pollution and Android Master Key, and is especially common in heterogeneous micro-services environments where protocols are loosely defined; addressing it requires a fundamental approach rather than merely patching individual bugs.