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

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4answers
4k views

What are the disadvantages of single sign-on authentication?

We were discussing to implement single on in our web application,right now after analyzing we came to know that the following were the advantages of single sign on authentication. Advantages Users ...
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1answer
223 views

WAF Process Creation for Integration of IT and Business

A client has asked me to help them out with their WAF processes. Currently they have a few critical web applications being protected by a couple of WAFs. I have managed to get the WAFs tuned and ready ...
10
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1answer
315 views

Is there a web application firewall equivalent of virustotal?

I'm wondering if there is a web application firewall (WAF) equivalent of VirusTotal? A site where I can throw for example injection strings, exploits or xss, and it will tell me what the default ...
10
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2answers
484 views

Is request signing (digesting the request body) in a REST API necessary?

I am currently engaged in a debate and I wondered what the community's opinion on this was. We see REST APIs which just require basic authentication (perhaps HTTP) or OAuth. We see REST APIs which ...
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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 ...
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1answer
686 views

How can I embed iframe securely without restricting its functionality?

I'd want to embed an iframe from untrusted site into web application. Iframe: should be able to run Javascript and browser plugins (Flash, etc.) should not be able to access my web application ...
10
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1answer
593 views

Webapp2 security

I am coding a REST web application that runs on Google App Engine, it authenticates API requests to privileged data using sessions by cookies provided by webapp2_extras.auth and ...
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6answers
500 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 ...
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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 ...
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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 ...
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4answers
275 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.
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3answers
365 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 ...
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3answers
876 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! ...
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4answers
495 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
326 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 ...
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5answers
8k 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 ...
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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. ...
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3answers
224 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 ...
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2answers
6k 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 ...
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2answers
11k views

Specific risks of embedding an HTTPS iframe in an HTTP page

I need help listing the specific risks of embedding an HTTPS iframe that enables credit card checkout inside of an HTTP page. Are there security issues with embedding an HTTPS iframe on an HTTP page? ...
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2answers
1k 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
1answer
474 views

XSS Technique - & JavaScript Include

I was looking through the OWASP XSS Filter Evasion Cheat Sheet, and there was one technique that was completely new to me: & JavaScript includes <BR SIZE="&{alert('XSS')}"> I ...
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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?
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4answers
284 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 ...
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4answers
541 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 ...
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4answers
982 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 ...
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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?
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3answers
785 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 ...
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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 ...
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3answers
3k 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, ...
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3answers
9k 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 ...
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2answers
487 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 ...
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3answers
741 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 ...
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1answer
893 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 ...
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2answers
2k views

How to protect against clickjacking attack but allow legit iframes?

I'm aware of modern anti-clickjacking approaches, such as X-Frame-Options header or framekiller scripts. But all these tactics prevent content to be inside iframe. But what if there is a requirement ...
9
votes
2answers
3k 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
899 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
331 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 ...
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votes
3answers
12k 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 ...
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votes
3answers
536 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?
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votes
9answers
383 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
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3answers
9k 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 ...
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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
585 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 ...
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3answers
7k 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
318 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
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2answers
303 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 ...
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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
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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 ...
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votes
4answers
783 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 ...