Flawfinder

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Flawfinder
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Contents

• Overview
• Environment
• Install Flawfinder
• Usage of Flawfinder
• Example
• How does Flawfinder Work?

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Overview

• Flawfinder search through C/C source code
  looking for potential security flaw.
• Flawfinder can integrate well with text editors
  and integrated development environments.

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Install Flawfinder

• Download Flawfinder
• http//www.dwheeler.com/flawfinder/

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Install Flawfinder (cont.)

• Unpacking the Package

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Usage of Flawfinder

• Synopsis

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Example wu-ftpd 2.6.0
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Example wu-ftpd 2.6.0 (cont.)
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Example wu-ftpd 2.6.0 (cont.)
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Example wu-ftpd 2.6.0 (cont.)
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How does Flawfinder Work?

• Flawfinder works by using a built-in database of
  C/C functions with well-known problems.
• Buffer Overflow Risks
• strcpy(), strcat(), gets(), sprintf(), and the
  scanf() family
• Format String Problems
• vfprintf(), vsnprintf(), and syslog()

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How does Flawfinder Work? (cont.)

• Race Conditions
• access(), chown(), chgrp(), chmod(), tmpfile(),
  tmpnam(), tempnam(), and mktemp()
• Potential Shell Meta-character Dangers
• Most of the exec() family, system(), popen()
• Poor Random Number Acquisition
• Such as random()

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Risk in the Hitlist