Get the basics right!
Hello World 2017
by Renato Rodrigues
Web Apps
Issues
Out of the Box
Out There
Web Applications
What IS it?
In computing, a web application or web app is a client–server software application which the client (or user interface) runs in a web browser.
https://en.wikipedia.org/wiki/Web_application
Concept
Modern Apps
Images from Google Images.
The Big Picture
Maybe we should know where they live!
We know that a modern Web App is a pile of technology.
How many
stacks are being used?
The
links between them?
Possible
weaknesses?
Can we understand:
Browsers
Images from Alrra Browser-Logos.
Issues
Cross-site scripting (XSS)
Cross-site Request Forgery (CSRF)
SQL Injection (SQLi)
Remote Code Execution (RCE)
XML External Entity (XXE)
Session Fixation
Dir Traversal
Insecure Direct Object References
Broken Authentication and Session Management
Server Side Request Forgery (SSRF)
Unvalidated Redirects and Forwards
Insecure Cryptographic Storage
Relative Path Overwrite (RPO)
...
OUT OF THE BOX
X-XSS-Protection
Sets the configuration for the cross-site scripting filters built into most browsers. The best configuration is "X-XSS-Protection: 1; mode=block".
X-XSS-Protection 1; mode=block
Information from SecurityHeaders.io
X-Frame-Options
Tells the browser whether you want to allow your site to be framed or not. By preventing a browser from framing your site you can defend against attacks like clickjacking.
X-Frame-Options SAMEORIGIN | DENY
Information from SecurityHeaders.io
X-Content-Type-Options
Stops a browser from trying to MIME-sniff the content type and forces it to stick with the declared content-type. This helps to reduce the danger of drive-by downloads. The only valid value for this header is "X-Content-Type-Options: nosniff".
X-Content-Type-Options nosniff
Information from SecurityHeaders.io
Content-Security-Policy
Is an "effective" measure to protect your site from several attacks. By whitelisting sources of approved content, you can prevent the browser from loading malicious assets.
Content-Security-Policy default-src 'self'; script-src 'self' ...
Information from SecurityHeaders.io
CSP Builder (Helper): https://report-uri.io/home/generate
Strict-Transport-Security
Is an excellent feature to support on your site and strengthens your implementation of TLS by getting the User Agent to enforce the use of HTTPS.
Strict-Transport-Security max-age=31536000; includeSubdomains; preload
Information from SecurityHeaders.io
Public-Key-Pins
Protects your site from MiTM attacks using rogue X.509 certificates.
By whitelisting only the identities that the browser should trust, your users are protected in the event a certificate authority is compromised.
Public-Key-Pins pin-sha256="t/OMbK...JM="; max-age=600; report-uri="..."
Information from SecurityHeaders.io
Subresource Integrity
Mechanism by which user agents may verify that a fetched resource has been delivered without unexpected manipulation.
<script src="https://example.com/example-framework.js"
integrity="sha384-Li9vy3DqF8tnTXu...gNR/VqsVpcw+T...Jr7"
crossorigin="anonymous"></script>
Information from W3C.
Cookies
Session, Secure, HTTPOnly and SameSite
Input Validation
Client and Server Side Always!
More to come: Suborigins, Referrer Policy, Expect-CT ...
Not out of box but...
Out There
BUG BOUNTIES
//cobalt.io - //bugcrowd.com - //hackerone.com - //synack.com
Search for a Security Page
A bug bounty program is a deal offered by many websites and software developers by which individuals can receive recognition and compensation for reporting bugs , especially those pertaining to exploits and vulnerabilities.
https://en.wikipedia.org/wiki/Bug_bounty_program
Report
Discovery Date: dd/MM/YY - HH:mm:ss System/Domain: https://sub.website.com/ Vulnerability Type: XSS / RCE / CSRF / ... Description: Detailed explanation of the vulnerability Impact: In the context of the vulnerable service/app. Proof of Concept Data (PoC) * Works in: Google Chrome, Firefox, IE, Safari, ... * Attack Vector: How to trigger the vulnerability. * Payload: What triggers the vulnerability. PoC Image/Video: Visual proof. Mitigation: If we have an idea how to fix, we should suggest. Notes: If pertinent.
Always remember to be polite!