OWASP 301: Infrastructure-based Security

Some of the trickier application security risks (ASRs) covered by the OWASP Top ten are focused on infrastructure and application configuration. As these risks are deeper within the production stack, they can be harder to find and address. Together, we’ll walk through each of these risks, examine how to identify them in an application or production environment, and cover actionable steps you can take today to address them with your application.

Transcript

1. OWASP 301:
   Infrastructure-Based Security
   Eric Mann
   

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2. ASR 3 - Sensitive Data
   Exposure
   

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3. Many web applications do not
   adequately protect sensitive
   data, such as credit cards, tax
   IDs, and authentication
   credentials.
   

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4. Photo borrowed from Schneier on Security:
   https://www.schneier.com/blog/archives/2005/02/the_weakest_lin.html
   

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5. Sensitive Data Retention
   What data do you retain?
   Why do you need this data in the first place?
   Who has access to the data?
   Where are backups stored?
   Who has access to the data via the backup system?
   

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6. Encoding is not
   encryption!
   

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7. function encodeString($str) {
   for ($i = 0; $i < 5; $i++) {
   $str = strrev(base64_encode($str));
   }
   return $str;
   }
   function decodeString($str) {
   for ($i = 0; $i < 5; $i++) {
   $str = base64_decode(strrev($str));
   }
   return $str;
   }
   encodeString('this is a secret');
   QVlRHZlbopUYxQWShRkTUR1aaVUWuB3UNdlR2NmRWplUuJkVUxGcPFGbGVkVqp0VUJjUZdVVaNVTtVUP
   

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8. ASR 5 - Broken Access
   Control
   

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9. Restrictions on what
   authenticated users are
   allowed to do are not properly
   enforced.
   

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10. $app->post( '/profile',
    function ($request, $response, $args) {
    if (!isset($_SESSION['user_id']) ||
    !$this->users->get($_SESSION['user_id'])) {
    return $response->withRedirect('/?error=notloggedin');
    }
    $userID = $request->getParam('user_id');
    $fname = $request->getParam('fname');
    $lname = $request->getParam('lname');
    $email = $request->getParam('email');
    // Retrieve the user's account from the database (via the app container)
    $user = $this->users->get(intval($userID));
    $user->profile->fname = filter_var($fname, FILTER_SANITIZE_STRING);
    $user->profile->lname = filter_var($lname, FILTER_SANITIZE_STRING);
    $user->profile->email = filter_var($email, FILTER_SANITIZE_EMAIL);
    $this->users->update($user);
    }
    );
    

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11. United Airlines experienced this vulnerability in their mobile app in 2015 -
    https://randywestergren.com/united-airlines-bug-bounty-an-experience-in-reporting-a-serious-vulnerability//
    

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12. ASR 6 - Security
    Misconfiguration
    

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13. Secure settings should be
    defined, implemented, and
    maintained, as defaults are
    often insecure.
    

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14. PHP Settings
    Disable error display (display_errors)
    Disable remote includes (allow_url_fopen and allow_url_include)
    Set reasonable resource maximums (upload_max_filesize and memory_limit)
    Leverage the disable_functions directive to block dangerous functions:
    exec, passthru, shell_exec, system, proc_open, popen,
    parse_ini_file, show_source, eval, create_function
    

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15. Webserver Settings (Nginx / Apache / etc)
    Disable server tokens and signature disclosure
    Configure a static server name (don’t trust potentially malicious HOST headers)
    Disable directory traversal
    ALWAYS configure strong SSL certificates for secure access
    Return proper error codes
    

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16. Database (MySQL) Settings
    Set an appropriate bind-address
    Ensure users are configured from the correct host, not a % wildcard
    Limit user permissions on the database to just what the application needs
    

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17. ASR 9 - Using
    Components with
    Known Vulnerabilities
    

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18. Applications using
    components with known
    vulnerabilities may undermine
    application defenses and
    enable a range of possible
    attacks and impacts.
    

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19. Audit Application Dependencies
    Monitor Composer-installed dependencies for outdated or vulnerable libraries
    Leverage unattended-upgrades to keep system packages up-to-date
    Audit the packages installed on your server - don’t install things you don’t need
    

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20. Custom error messages can help demonstrate when a security hole has been plugged. Or
    annoy those who were exploiting it in the first place...
    

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21. Audit Application Dependencies
    Monitor Composer-installed dependencies for outdated or vulnerable libraries
    Leverage unattended-upgrades to keep system packages up-to-date
    Audit the packages installed on your server - don’t install things you don’t need
    Only run current, supported versions of PHP!!!
    

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22. ASR 10 - Insufficient
    Logging & Monitoring
    

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23. Attackers rely on the lack of
    monitoring and timely
    response to achieve their
    goals without being detected.
    

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24. It’s Important to Track:
    What happened
    When it happened
    Where it happened (in terms of code and the IP of the server)
    To whom it happened
    What input triggered the event
    

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25. Event Classes
    Input Validation Errors
    Output Validation Errors
    Authentication Events
    Authorization (Access Control) Failures
    Application Errors
    Application Startup/Shutdown
    High-risk Operations
    

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26. (Full image slide. No text)
    

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27. Questions?
    

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28. Thank you
    eric.mann@vacasa.com | 503.925.6266
    

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