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

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9
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4answers
286 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
votes
2answers
5k views

Why does Hydra return 16 valid passwords when none are valid?

I've been playing around with Hydra and DVWA and I've hit a bit of a snag - Hydra responds letting me know that the first 16 passwords in my password list are correct when none of them are. I assume ...
9
votes
3answers
213 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
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
3answers
2k views

Using file extension and MIME type (as output by file -i -b) combination to determine unsafe files?

We allow users to upload a number of files, all of which we either send over to scribd (doc, xls, ppts, etc) or display as a video ourselves (flv, mov, mp4, etc in flowplayer). To avoid users ...
9
votes
2answers
902 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
4answers
495 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
824 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
3answers
199 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
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
1answer
715 views

How is time-based SQL injection different from other types of SQL injection?

I understand what a time-based SQL injection is, and I understand how it works (at least how it's detected/exploited). However, is there anything in specific which makes this type of injection any ...
9
votes
3answers
635 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
2answers
418 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
674 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
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
757 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
317 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
9k 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
474 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
374 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
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
307 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
298 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
3answers
311 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 ...
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
640 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
972 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
4answers
2k 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
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 ...
8
votes
6answers
3k 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. ...
8
votes
2answers
233 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
2k 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?
8
votes
2answers
331 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
4answers
644 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
559 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
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
2answers
3k views

Is doing credit card transaction via 3G secure?

3G, GPRS or other mobile-based connection. Because it seems like it's easier to intercept, than, say, land-based connection or encrypted WiFi. If it matters, the transaction I want to perform is ...
8
votes
3answers
260 views

Verify a website user is behind corporate firewall?

We have a public ecommerce website hosted at our datacenter onsite. For people who are within the corporate firewall hitting the website I want to display profiling information about the request of ...
8
votes
5answers
1k views

Websites that interactively test browser security (XSS, CSRF, Javascript, etc)

I'm looking for a comprehensive list of browser test sites so that I can visually prove that the browser is patched and configured for safe web browsing. My intent is to know what risks may exist ...
8
votes
2answers
855 views

MIME sniffing protection

As it is known, older versions of MSIE (before 8) have a nasty habit of treating images as HTML if they "look like" HTML, which can lead to nasty vulnerabilities for sites that allow people to upload ...
8
votes
3answers
414 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 ...
8
votes
2answers
508 views

Slowloris attack?

Could someone analyze this info? We got information that slowloris attack took place. They say (hosting stuff) they have implemented mod_antiloris, is that enough btw? Feel free to share your opinion ...
8
votes
3answers
1k views

Encrypting user data using password and forgot my password

I am planning to do a web application which stores a lot of personal stuff (info, photos...). And to give users a sense of protection, I want to encrypt the data before storing it to the database. ...
8
votes
1answer
493 views

Are browser still vulnerable to Cross-Site Cooking?

The latest article that I have been able to find about Cross-Site cooking was stating that it was possible to set cookie on 2 dots top level domain such as .co.uk. The mechanism for preventing ...
8
votes
1answer
792 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 ...
8
votes
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 ...
8
votes
2answers
1k views

How secure are the default ASP.NET membership and role providers for Sql Server?

I have a very basic idea of how these work. I've used them many times when I needed a user management system rather then writing my own. But should I use these for a production system? Would ...
8
votes
1answer
974 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 ...
7
votes
3answers
2k views

What kind of attack was this?

So our website was hacked, and these are the things that were done: Some entries in the database were changed. I don't know if this was via SQL injection, or direct database access (only root is ...