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Mozilla Observatory First Draft
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luke crouch
March 15, 2021
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Mozilla Observatory First Draft
luke crouch
March 15, 2021
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Transcript
Luke Crouch For learning and doing web app security
Me Luke Crouch • Privacy & Security Engineer, Mozilla •
Board member, Techlahoma Foundation • I’ve had 4 cups of coffee already ☕ ☕ ☕ ☕
This talk • 112 slides in ~15m • Mozilla Observatory
• Website • Command-line tool • API • Questions
How many of you use a tool to scan your
web site or app for security issues? 🙋
In Mozilla research, 16% say Yes n=1,181 web engineers *old
data
In Mozilla research, 47% say No n=1,181 web developers *old
data
Why don’t you use something to scan your web site
or app?
40% say: I don’t need it
Can’t have security vulnerabilities … … if you don’t know
about your security vulnerabilities.
17% say they “need to” use a tool
THANK YOU!
Because even if your app or site may not seem
like a target …
Your users may be re-using their password …
• their bank • their PayPal • their workplace •
their healthcare provider • their password manager (!) • their computer • etc. • their email • which gives an attacker access to all of those others!
So if your app is hacked, their other accounts could
get hacked too.
Next (rhetorical) question …
Which of the following security tech applies to your code?
• Mixed Content • Subresource Integrity • Cross-Origin Resource Sharing • Cookies • Secure • HttpOnly • Content Security Policy • HTTP Strict Transport Security • Redirections • Referrer Policy • X-Frame-Options • X-XSS-Protection • X-Content-Type-Options
🤷🤷
Which of the following security tech applies to your code?
• Mixed Content • Subresource Integrity • Cross-Origin Resource Sharing • Cookies • Secure • HttpOnly • Content Security Policy • HTTP Strict Transport Security • Redirections • Referrer Policy • X-Frame-Options • X-XSS-Protection • X-Content-Type-Options
How do you know what you need to know?
Luke Crouch For learning and doing web app security
None
None
None
None
None
None
Observatory helps me focus on learning the most important security
for my code right now.
Because the reason most of us don’t do all this
… • Mixed Content • Subresource Integrity • Cross-Origin Resource Sharing • Cookies • Secure • HttpOnly • Content Security Policy • HTTP Strict Transport Security • Redirections • Referrer Policy • X-Frame-Options • X-XSS-Protection • X-Content-Type-Options
we don’t have time to do it all.
But, there’s plenty of “quick wins” you can get with
a little bit of time
So, let’s get started …
⚠ Disclaimer: don’t be evil ⚠
You should only use security scanning and testing tools with
permission
So … don’t go scan a bunch of government websites
Now … let’s go scan a bunch of government websites
hackerone.com
None
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None
So basically, GSA gives permission to scan some sites, within
certain scope and under certain conditions
None
Let’s try the first one on the list: itdashboard.gov
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Loading external scripts over (insecure) HTTP - WCGW? 🤷
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https://itdashboard.gov <html> <head> … <script src=“http://ajax.googleapis.com/…”></script> … </head> … </html>
https://itdashboard.gov <script src=“http://ajax.googleapis.com/…”></script> HTTP HTTP
None
None
https://itdashboard.gov <html> <head> … <script src=“http://ajax.googleapis.com/…”></script> … </head> … </html>
None
https://itdashboard.gov <html> <head> <script src=“http://ajax.googleapis.com/…” integrity="sha384-R4/ztc4ZlRqWjqIuvf6RX5yb/v90qNGx6fS48N0tRxiGkqveZETq72KgDVJCp2TC" > </script> </head>
</html>
None
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https://www.keycdn.com/support/what-is-mime-sniffing
https://itdashboard.gov <script src=“/user-uploads/image.jpg”></script> /user-uploads/ js in image.jpg file js in
image.jpg file
None
Does your server set the right Content-Type for scripts and
styles?
Yes?
This is “easy” - you can add: X-Content-Type-Options: nosniff across
your entire server.
X-Content-Type-Options is the first recommended fix, because it’s easier than
others …
No?
Do you need to support old IE browsers? • No?
• add X-Content-Type-Options: nosniff • Yes? • Sorry to hear that • Does your site need to render user uploads in pages? • No? add X-Content-Type-Options: nosniff • Yes? • Sorry again …
This is how improving your security works
1. Find a potential vulnerability 2. Learn about the potential
attack(s) 3. Determine how much if affects your code specifically 4. Make an appropriate fix 5. Repeat
So, what’s next for itdashboard.gov ?
Normally, you would make the recommended fix …
None
And then
But since GSA won’t give us access to deploy code
on itdashboard.gov …
Let’s just check out the other tests in the report
…
None
None
X-XSS-Protection
None
None
But what does it actually do?
None
https://itdashboard.gov/?param=<script>alert(1)</script> <html> <head><title>…</title></head> <body> <?php echo $_GET[‘param’] ?> </body> </html>
X-XSS-Protection: 1; mode-block
https://itdashboard.gov/?param=<script>alert(1)</script> <html> <head><title>…</title></head> <body> <?php echo $_GET[‘param’] ?> </body> </html>
None
You might as well take care of older browser users
(they need all they help they can get!)
Do you need to render HTML from url params? •
No? • add X-XSS-Protection: 1; mode-block • Yes? • No you don’t. add X-XSS-Protection: 1; mode-block • For real you do? • No, for real you don’t.
None
Observatory Command-Line Interface
npm install observatory-cli
observatory itdashboard.gov --zero --format=report
None
So, same tests and results
Note: no “Recommendation”
But you could put this in your CI pipeline to
scan a dev or stage site on every code change
And you can make CI fail if the score drops
below a certain level
None
Observatory API
https://github.com/mozilla/http-observatory/blob/master/httpobs/docs/api.md
https://http-observatory.security.mozilla.org/api/v1 • POST /analyze?host=itdashboard.gov • hidden=true&rescan=true • GET /analyze?host=itdashboard.gov •
returns a “scan object” with a scan ID • GET /getScanResults?scan=<scan ID>
Now, let’s scan ALL the GSA sites in scope …
None
None
⚠ Disclaimer: don’t be evil ⚠
You should only use security scanning and testing tools with
permission
Questions • Mozilla Observatory • Website • Command-line tool •
API • 3rd-party scans • What else?
Appendix
None
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None
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None
So, let’s go see where itdashboard.gov might be vulnerable?
None
View source …
None
src=“http:// Phrase not found 🤔
None
“or use protocol-relative URLs” like src=“//
None
So, if someone accessed this page via insecure http:// ,
we could hack the script
But, if someone accessed this page via insecure http:// ,
we could just hack the page
So when would this ever be a real problem?
When would someone ever access this page over insecure http://
? 🙋
What if someone types “itdashboard.gov” without https?
What if another page links to “itdashboard.gov” without https?
When would someone run this page over insecure http:// ?
When would someone run this page at http://127.0.0.1 ?
None
None
None
Content Security Policy … what’s that?
Insert lots of content about CSP