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

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3answers
1k views

How to perform penetration testing on a Flex application?

Possible Duplicate: What tools are there to inspect Flash SWF files? I have decompiled it, verified the source. All seems fine. Appscan also is not able to find anything in this case. But I ...
9
votes
6answers
499 views

What are web attacks which users can run code on your servers?

I hear stories about insecure web servers and sites which people (or bots) break into and execute their own code on the server. My question is how is that possible? I heard of people putting their ...
9
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5answers
1k views

Ads appearing in our application when they should not be

I received a strange issue reported by one of my web application users. Apparently they are getting "ads" within the browser window when using my application. I didn't add advertisements at all. It's ...
9
votes
3answers
2k views

Is it possible to forge a post request?

Consider the following URL http://mysite.com/form?date=x. Suppose that if x is in an incorrect format, that a page is returned with <p>x is not a valid date</p>, where the page author has ...
9
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4answers
271 views

What are the main security considerations that must be taken into account if you intend on creating a (localised) whistleblower website?

Also: Is it something that can be achieved with limited funds? I ask because I am intrigued by the obstacles that are in place.
9
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3answers
343 views

How could the string \";alert('XSS');// be used for XSS?

I was using Burp Suite for some testing and I noticed that they included the following string: \";alert('XSS');// as an attack string for an XSS payload. How could this string be used to execute ...
9
votes
3answers
853 views

How do I secure my SaaS startup?

I came across this question I like to offer my startup also for security advice. Objective: building a SaaS web application that allows businesses to quickly open up online stores akin to Yahoo! ...
9
votes
4answers
487 views

Does my UI need to be secure if my API is?

I'm working on a project that is creating two new, separate web modules (possibly even on different servers) to support a new web application, with one serving up a static JS-based UI and the other ...
9
votes
4answers
308 views

When changing a password using a WebPage, must the old password be entered on the same screen?

There is a convention to always prompt for the old password on the same page as the one where the old password is being changed as shown below. Is it acceptable from a security perspective to allow a ...
9
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6answers
4k views

Why is php not used for banking sites or for a banking transaction?

Other programming languages popular on the web, such as Java and .NET, are used for banking sites. However, I've rarely (if ever) seen a PHP application designed to be deployed for a banking site. ...
9
votes
3answers
219 views

What simple security considerations can I / should I make for a read-only API?

Right now I'm setting up an API, to be consumed on the client-side to set up a directory site. I'm wondering what extra steps I need to take just to prevent people from gaining write access to the ...
9
votes
2answers
5k views

Implications of Trace/Track Methods on Apache

When performing vulnerability scans using Nessus, against a host running Apache, one expected result is always "HTTP TRACE / TRACK Methods Allowed". While this result only has a base CVSS of 4.3, I ...
9
votes
4answers
3k views

Generate cryptographically strong pseudorandom numbers in Javascript?

Is there any good way to generate cryptographically strong pseudorandom (or true random) numbers in Javascript? The crucial requirement: if a.com's Javascript generates some random numbers, no one ...
9
votes
2answers
980 views

Security Concerns on clientside(Javascript)

We are going to design and implement a UI for a big website. Owner of the site is really cautious about security issues. I wonder if there is a check list for security issues at the client-side ,while ...
9
votes
2answers
3k views

What can an attacker do with a stolen SSL private key? What should the web admin do?

What can an attacker do with a stolen website certificate and key? What should the website admin do upon learning this?
9
votes
4answers
271 views

Defending site against being abused by phishing

Say you have a web site and you are using some returnUrl URL parameter to redirect user back to page where he was after login or editing some records in user area. Is there some standard way how to ...
9
votes
4answers
530 views

Worthwhile from security standpoint to limit database server user for ASP.NET website to only EXECUTE on stored procedures?

I know that obviously we must avoid sql injection attacks through user input validation and parametrized queries. There's already a firewall in place on the database server to limit remote ...
9
votes
4answers
916 views

Is there a typical step-by-step A-Z process for testing a Web site for possible exploits?

I'm interested less in the tools of the trade (there are many questions here already about that), and I am interested more in the process by which you would go about using those tools. So for ...
9
votes
4answers
1k views

What is the right way of storing database connection strings from the security point of view?

What are recommendations, best practices and have-to-dos regarding handling connection strings in web applications? What things one should never, ever do?
9
votes
3answers
724 views

AES using derived keys / IVs. Does it introduce a weakness?

I'm looking for an efficient way to encrypt multiple fields in a database with AES using a single global key, used throughout a large web application. Obviously in order to re-use this key, a unique ...
9
votes
3answers
1k views

localStorage for apps over https. What expectations are there?

I run an online gradebook. To keep student data private, I transfer all data over https. Now, I'd like to use localStorage to avoid redundant calculations and server requests. However, according to ...
9
votes
3answers
2k views

Is “Why Should You Avoid AES In MySQL?” true?

From a 2012 Smashing Magazine article quite a bold statement is made to avoid AES in MySQL itself. Or as they put it "Why Should You Avoid AES In MySQL?". However, if you search for SQL encryption, ...
9
votes
2answers
465 views

User-specific Subdomains : JavaScript security

If I provide a public-facing website for users on my website at their own subdomain (e.g. bob.myapp.com) under their own control, can I allow them to execute arbitrary JavaScript without putting my ...
9
votes
3answers
716 views

If I am obliged to store a password/certificate on a client side, how can i make sure that it is protected?

In certain cases we need to establish a key/password/certificate as a first timer and then as a client we need to use this key/password/certificate to get authenticated. Therefore the ...
9
votes
1answer
868 views

How to make SQL injection in PostgreSQL's tsquery?

I think there is SQL injection vulnerability in an application I'm testing. This is seen when I enter malformed parameters into a search form. All exceptions are shown in format: PHP raised unknown ...
9
votes
2answers
2k views

Keeping user session alive - security considerations

We have recently developed some functionality for our web app to allow a user to remain logged in indefinitely, and are interested in knowing the security ramifications of doing so. The goal of this ...
8
votes
6answers
839 views

when is it safe to click through an SSL warning message?

How does a user know if it's safe to click through scary browser warnings about SSL certificates? Ideally, a user should never need to click through these warning messages, but sometimes honest ...
8
votes
7answers
329 views

Aren't permanantly logged in accounts inherently insecure?

The basic premise behind a "keep me logged in until I log out" feature is a cookie is stored with some identifier that is used to log the user in again when returning to the site. While these ...
8
votes
3answers
11k views

Is there any SQL injection for this PHP login example?

I want to write a login form, and I got one example from the web. I want to know, if there is any SQL injection for this code? If there is, what could the exploit's web form entry look like? This is ...
8
votes
3answers
501 views

How does an attacker approach a website?

What is a typical mindset and method of approach? What are they likely to try first? At what point does a novice give up versus an expert? How would an automated attack differ from a manual one?
8
votes
9answers
378 views

What is the proper way to view the sourcecode of a website?

I recently heard that Firefox makes a second HTTP request when the sourcecode is requested. Is this true? Does this mean the webserver may issue alternate source from the original? Lastly, is ...
8
votes
3answers
8k 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 ...
8
votes
4answers
2k views

Is using HMAC to transmit a password OK?

I'm writing a small webapp and I don't want to transmit login passwords as cleartext. As I don't have SSL available I've written a one-time challenge system which sends a random string with the login ...
8
votes
3answers
574 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 ...
8
votes
3answers
6k 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 ...
8
votes
3answers
310 views

Does concealing server software versions have a notable effect on security?

Web servers can add Server, X-Powered-By and similar headers into HTTP responses. Looks like the consensus is such headers should be removed so that automatic vulnerability scanners don't immediately ...
8
votes
2answers
299 views

What is secure enough for web applications?

we intend to build a network in a small health center with No Internet Access it is expected to have 30 terminal machines, all machines will use an electronic medical record web application we want ...
8
votes
6answers
4k 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, ...
8
votes
3answers
5k views

What SSL key should I make for IIS: RSA or DH? What bit length is appropriate?

I'm creating an SSL cert for my IIS server and need to know when I should choose the Microsoft RSA SChannel Cryptographic Provider or the Microsoft DH SChannel Cryptographic Provider. Question 1 Why ...
8
votes
4answers
732 views

How dangerous is it to store password in plain text on sites like GitHub?

I have a few private repositories set up on GitHub for some of the projects I am working on for my company. These applications connect to databases and I have database authentication credentials ...
8
votes
3answers
1k views

How bad is a Self Contained XSS attack?

Some of you might be familiar with this attack called Self Contained XSS. I recently stumbled upon this article about it. So how bad this kind of attack can be, even though this doesn't have access to ...
8
votes
3answers
214 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 ...
8
votes
4answers
3k views

How effective are reverse proxies as a web application security measure?

How effective are reverse proxies as a web application security device? Which types of threats do they mitigate against and which don't they? For example are they more effective in preventing ...
8
votes
4answers
3k views

Is it okay for API secret to be stored in plain text or decrypt-able?

Aren't API keys considered usernames and API secrets considered passwords? Why is it that API servers like Amazon Web Services allow you to view your API secret in plain text? It makes me think they ...
8
votes
2answers
242 views

Is there any risk related to allow user to give an URL as their image profile?

Building a website, I'd like to allow users to specify an url that point to an image that will be used as a profile picture (included in the HTML DOM as a ). But before doing anything stupid, I was ...
8
votes
2answers
380 views

Isolating Web application hosted on same web server

I am working on a scenario if we have two or more web application hosted on a same server. Let says Web application X is vulnerable so how can i be sure that it will not effect the other web ...
8
votes
3answers
2k views

Should web sites disable form autocomplete on all forms?

I've noticed that some web-app security scanners flag the 'Autocomplete' feature of some websites (in the username/password fields) as a security risk and thus suggest including "AUTOCOMPLETE = false" ...
8
votes
4answers
730 views

Preventing insecure webapp on subdomain compromise security of main webapp

I want your help on getting more concrete information on a type of vulnerability that I remember vaguely. I vaguely remember hearing about a year ago that if you set up a webapp on a subdomain, and ...
8
votes
2answers
583 views

Recent Facebook XSS exploit details

There was a recent XSS exploit on Facebook that posted a vulgar message and got users to click on a link to spread the payload. What vulnerability was exploited, and what can other sites do to avoid a ...
8
votes
3answers
445 views

What security features should be present in every web-based CMS?

What are the most important security features that a web-based CMS should offer? What's vital? What would be nice to have? What features should the CMS not attempt to do? Please note: I'm looking ...