I'm currently doing front-end development for an insurance companies client portal and one of their developers is concerned about using typekit for security reasons. Does anyone know if there is a legitimate risk in using typekit on secure sites? Also, if anyone has some documentation on this that I could send to this developer that would be really helpful, I (surprisingly) wasn't able to find anything on the typekit site that would put his mind at ease.
Thanks!
There are different ways of including Typekit fonts. When you host your own CSS with #font-face rules pointing at font files on Typekit servers that's generally fine.
In this case Typekit will receive the URL of the page the user is browsing as a referrer, but there should not in general be sensitive information in the URL so that should be OK. (That may not be true if you have something like a reset password link - if you do, take care to ensure such URLs can only be accessed once so the ID in the link is worthless afterwards.)
However there is a variant where you include a script tag pointing at them:
<script type="text/javascript" src="https://use.typekit.com/some_id.js"></script>
This is a bad idea if your site does anything sensitive, because it gives typekit complete control over everything a user does on your site. If they went evil (or were compromised), they could steal any passwords typed on your site, delete all the user's data on the site, redirect the user to browser exploits, and so on.
In general you should never include remote scripts or stylesheets from anyone you don't 100% trust with the security of your site.
Any time you embed content, whether it be JS, CSS, fonts or anything else, from an external source to a sensitive page, you're increasing your attack surface. This does not necessarily mean that there is, or will be, a specific attack, but it does create more potential ways in which your site could be compromised.
Indeed, there have been real-world attacks using web fonts even without JavaScript, both based on browser / OS bugs and simply based on interactions of deliberate browser features. The Firefox security extension NoScript blocks CSS #font-face by default for that reason.
If you want to use a custom font on your secure site, the safest way to do it is to host it yourself — either on the site itself, or, perhaps better yet, from a separate no-cookie domain which is under your control, but isolated from your main website content by browser same-origin policies.
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Apart from all the other typical security best practices I'm wondering about this, since I lately read some articles talking about how browser extensions can spy anything their user does. So that we shouldn't trust them.
Therefore in order to give users and additional layer of protection should I process all users credential and sensitive info inside an iframe inside my webpages?
Can content inside a sandboxed iframe be read/spied by browser
extensions?
Yes
Could I use iframe to secure user credentials?
Quick answer, no.
When a user installs a chrome extension the extension can do basically anything in the website to access the user credentials. The extension has also access to the iframes that the page generates.
My proposed solutions to overcome this two issues and keep the website feel "secure" are the following:
If the end goal is to secure the content that your user will put in the website, and by no mean you want to let the user put content if there are other kind of extensions running in the page, what you can put is some kind of pop up in the page blocking the access to the user until he is accessing the website without extensions.
Another solution you could propose to the user is to go incognito mode, as there are many options to disallow extensions in incognito without having to force him to uninstall all of the extensions that he has on his browser. This could also make less users leave your page, as if you force him to uninstall of the extensions on his browser it might make him leave your page if it's not a clear enough reason for him.
If you do know which are the extensions that shouldn't be blocked or prevented because they are harmful or known to have some kind of shady behaviour, what you can do is checkout if the user has them installed with this solution Checking if user has a certain extension installed and then print a message to him saying he can't continue until he uninstalls those extensions.
My webmaster has an online store on a site with ssl that i would like to feature on my site. He says this could be done with an iframe. Are there any security risks in using an iframe for this shop, in example a middle man attack? Or is this safe for any customers using it because the origin is protected?
Although iFrames are, in theory, loaded securely in their own environment, there are several security issues with them including:
They can be used for ClickJacking attacks. For example a site loads another website in an iframe and then floats username and password text boxes on top of the iframe so people think they are typing these into the website in the iframe, when in fact they are not.
It's not easy to see the website the iframe is loading. For example you load a frame of badbank.com and make it look exactly like goodbank.com. The user has no idea which domain has loaded as there is no address bar nor green padlock.
In general it's suggested for websites to prevent framing using X-Frame-Options or Content Security Policy HTTP Headers to prevent framing.
For sites like you doing the framing (rather than being framed) you are therefore risking your users. So if your site is hacked then this might lead to above issues. Additionally I've worked on a couple of sites where framing suddenly broke when the framed site prevent it from being framed anymore using above headers. Which looks bad on your site.
Finally framing breaks some of the fundamental ways of using the web (e.g. Back button).
All in all I would caution against iFrames.
I have been reading a lot regarding iframes and clickjacking, and was not able to find the information I am looking for. Can you help me out with below questions?
How does Iframe clickjacking spread? I have seen lot of articles which mentions editing of html code in the local machine and by the same they are able to hijack users click by adding an invisible button. But, this is a modified logic on a local machine of a user. I am interested in knowing is it possible to push this same code to the cloud and impact every user logging in or using that portal? If yes, how?
If I enable Iframe options on my website, it is a security risk because my page can be loaded as an Iframe in some one else's website and they can misuse it. And if there is any secured data, if end user is accidentally entering on that website, the data is hacked. This is a security concern so it is always recommended not to allow Iframe, is that correct? Are there any other security risk.
Please add if there are any other risks.
Clickjacking does not spread.
It is literally as it is stated - jacking clicks - nothing more. However, the consequences of those clicks could be severe.
Imagine you visit a site, evil.example.org. In another tab you are also logged into your bank, bank.example.com.
evil.example.org also loads bank.example.com in an IFrame. However, it uses CSS to make this IFrame invisible. And it does not load the home page, it loads the money transfer page, passing some parameters:
<iframe src="https://bank.example.com/loggedIn/transferMoney?toAccount=Bob&amount=100000"></iframe>
Now, this page does not transfer the money immediately. It asks the user to click to confirm the transfer to Bob.
However, evil.example.org draws a button right underneath the Confirm Transfer button saying Free iPad click here.
Because the IFrame is invisible, the user just sees Free iPad click here. But when they click, the browser registers the click against Confirm Transfer.
Because you are logged into the bank site in another tab, Bob has just nicked your money.
Note that the X-Frame-Options header fixes this vulnerability on your site, assuming it is set to SAMEORIGIN or DENY. You are vulnerable until you add the header. There's a new directive in CSP called frame ancestors - however, only the latest browsers support it, so you're best off adding both headers at the moment. This will give you protection on Internet Explorer 8 and later, plus Chrome, Firefox, Opera and Safari.
Preventing framing can also help thwart over attacks such as Cross Site History Manipulation.
I was wondering if it's possible to capture a screenshot and/or record my computer screen(s) via a website?
If it is possible, what languages would I need to learn/code? I already have intermediate knowledge of HTML, CSS, JavaScript, jQuery, and PHP.
In other words: I want to have the ability to capture/record my screen (not the website) via using a website (not an application).
Thanks!
This is not possible. Web sites are very deliberately given only restricted access to your computer for security reasons. Imagine the havoc that could result if a malicious web site were able to see and capture what was on your screen--banking information, your confidential e-mails, etc. Even if the user had to give permission for this level of access, it would still be way too easy to trick a user into giving that permission.
The closest I could find/think of was http://www.screencast-o-matic.com/screen_recorder, but even then you have to download a launch plugin. I agree with #DLH. This is for your protection.
My favorite screen recorder is ScreenPresso - it is always running in background, and repurposed the PrtScn button as its launch key.
I want to allow my users to embed their own Flash animations in their posts. Usually the actual file is hosted on some free image hosting site. I wouldn't actually load the flash unless the user clicked a button to play (so that nothing auto-plays on page load). I know people can make some really annoying crap in flash, but I can't find any information about potential serious damage a flash app could cause to the viewer.
Is it unsafe to embed just any flash file from the internets? If so, how can I let users embed innocent animations but still keep out the harmful apps?
edit:
From what I can gather, the most obvious threat is for actionscript to redirect you to a malicious site.
Adobe says you can set allowScriptAccess=never and allowNetworking=none and the swf should have no access to anything outside of itself. Will this solve all my problems?
Flash has some neat security measures in place. Allowing users to upload swf's to your site and embedding them is unsafe, you're basically setting yourself up for an XSS attack.
However, allowing them to hotlink should not be a problem. The swf will be locked to the domain that is hosting it and is not allowed calling url's outside of that space.
It will still be open to "evil links" (i'm sure theres a proper word for them), and by that I mean having regular links to yoursite.com/admin/deleteallpages.php which it tries to load "as" you. It will not however be able to use this data in any way, it'll basically be the same as a normal link, and I'd guess modern cms' are protected from that type of attacks.
You could get the same protection by hosting your flashes on a different subdomain, since flash considers this the same as a completely different domain.
When embedding SWFs from unknown sources, it is also best practice to throw a mask on the Loader so that the loaded SWF can't take over more screen real estate than expected.
Pseudo-code to do so:
var maskSpr : Sprite = new Sprite();
maskSpr.graphics.beginFill();
maskSpr.graphics.drawRect(0,0,safeWidth,safeHeight);
maskSpr.graphics.endFill();
myLdr.mask = maskSpr;
There is actually more than one option.
To be totally safe, set allowScriptAccess=never and allowNetworking=none and the swf will have no access to anything outside of itself.
NOTE: allowNetworking is only in Flash Player 9 (it was created in response to various myspace worms), so you'll need to use SWF Object to insure that only users with the right flash player version or better have the flash loaded.
If you want to enable things like youtube videos, though, you can't set allowNetworking to "none". Fortunately, there is an intermediate level of security for this field - "internal" which lets the SWF talk to its hosted domain.
Also note that you better not have a crossdomain.xml file on your site - read more about those dangers here and other places.
Here are some other sites that are mentioned by other answers that go into more detail:
http://www.adobe.com/devnet/flashplayer/articles/secure_swf_apps_04.html
http://blogs.adobe.com/stateofsecurity/2007/07/how_to_restrict_swf_content_fr_1.html
As an example Drupal has a scenario of how allowing flash content from users could be a security concern.
Adobe says you can set allowScriptAccess=never and allowNetworking=none and the swf should have no access to anything outside of itself. Although allowNetworking is only in Flash Player 9, so users with earlier versions of Flash would still be susceptible to some exploits.
Creating more secure SWF web applications : Security Controls Within the HTML Code
How to restrict SWF content from HTML
Yes, it's unsafe.
There's no easy way of allowing it. You could have a domain whitelist that allowed YouTube, Hulu, etc. through, but whitelisting is inherently painstaking - you'd be constantly updating.