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

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11
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3answers
841 views

Is Gmail showing images by default a good idea for privacy?

Google have decided to show images in Gmail messages accessed via the web, iOS and Android by default: Instead of serving images directly from their original external host servers, Gmail will now ...
11
votes
3answers
1k views

How much information about the reason for an unsuccessful login should a web application give?

After an unsuccessful login attempt, should I inform the user about its reason? Or more generally, how much information about the reason for an unsuccessful login attempt should a web application ...
11
votes
1answer
560 views

Public XSLT & XML playground (with PHP DOMDocument, etc.) Security Risks?

Let's say I want to set up a sandbox or playground in PHP that users can use to create (or paste in) XML and XSLT, then transform the XML via the XSLT (by means of PHP 5's DOMDocument and related ...
11
votes
1answer
2k 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 ...
11
votes
2answers
1k views

Security quiz for developers

Does anyone know of a short security quiz that could be administered online, to test the security knowledge of a developer? I'm looking for something simple to administer and simple to grade, ideally ...
11
votes
4answers
4k 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?
11
votes
1answer
319 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 ...
11
votes
1answer
820 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 ...
10
votes
3answers
7k views

How secure are sha256 + salt hashes for password storage [duplicate]

I started reading about password hashing recently on multiple sites like this page on crackstation and others, and for what I have understood, I should avoid using hashing algorithms like md5 and sha1 ...
10
votes
6answers
634 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 ...
10
votes
6answers
4k views

Security review: “HTTP header user-agent has been set to (something)”

We got a security review done of our PHP code and they team advised this in their report (amongst other things): /appdir/ Details The HTTP header user-agent has been set to \" . Request GET ...
10
votes
4answers
5k 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 ...
10
votes
4answers
574 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 ...
10
votes
6answers
10k 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. ...
10
votes
4answers
511 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 ...
10
votes
2answers
1k 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 ...
10
votes
3answers
578 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 ...
10
votes
4answers
20k views

Better techniques than url parameter encryption

I'm a programmer working on an application where the only choice/vs/deadline was to implement symmetric encryption on url parameter values. The data is insensitive in nature, but we needed to prevent ...
10
votes
3answers
3k 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 ...
10
votes
3answers
504 views

Should I ask a user to re-authenticate if the browser thumbprint changes? Is a server side library available?

Is there a security benefit to using the browser's thumbprint in addition to a session identifier to identify a unique session? Would it then be advisable to ask the user to reauthenticate (or simply ...
10
votes
2answers
1k views

What are the SQL-injections issues of parameterized queries?

I've written some code to generate an SQL query in ASP classic. I'm not sure if it's secure or not: Set adoCon = Server.CreateObject("ADODB.Connection") adoCon.Open "Provider=Microsoft.Jet.OLEDB.4.0; ...
10
votes
5answers
5k views

Does setting httponly prevent stealing a session using XSS?

If a session token is stored in a cookie that has httponly set, is there any way that a XSS vulnerability could allow a malicious user to steal a users session token?
10
votes
3answers
3k views

What is the next step of this file upload attack?

Yesterday I discovered somebody had uploaded this PHP code to my server as a .jpg file via my asp.net MVC application's "Upload your profile picture" form. I believe the attack was unsuccessful for a ...
10
votes
4answers
2k 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 ...
10
votes
2answers
683 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 ...
10
votes
3answers
722 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 ...
10
votes
4answers
417 views

What are the drawbacks of login request throttling?

In a web application, one way to protect against password guessing attacks is to lock out accounts after a set number of failed logins. This could be done on both source IP address and username. For ...
10
votes
3answers
8k 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 ...
10
votes
1answer
3k views

How to use postMessage securely

postMessage is a primitive introduced in HTML5 that web pages can use for cross-origin communication. What do I need to do to use postMessage securely? What are the primary security pitfalls or ...
10
votes
3answers
1k 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 ...
10
votes
4answers
9k views

Is client side encryption really better than server side?

Web application may encrypt all user data at client side to convince users that it can't decrypt them. When user enters password, it's used to encrypt data in browser and then it's sent to server in ...
10
votes
1answer
409 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
votes
2answers
3k 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 ...
10
votes
3answers
2k 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 ...
10
votes
1answer
3k views

Does it make sense to implement OAuth when no 3rd party is involved

I own a REST API at server side and a distinct web application that would call those APIs. I want to secure my APIs calls. After some reading, I want to implement the OAuth 1.0a mechanism at server ...
10
votes
1answer
960 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
votes
1answer
197 views

Using certificates to secure

I'm working on an application that comprises of a C# WebAPI (on Azure Websites) and a native mobile app. Essentially, a client creates a series of messages using a Web interface and these can be ...
9
votes
6answers
2k 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 ...
9
votes
3answers
2k 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: ...
9
votes
7answers
405 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 ...
9
votes
3answers
25k 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 ...
9
votes
3answers
3k 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
votes
2answers
2k views

When viewing my website from port 3306, I see some weird MySQL info

If I visit my web URL and force port 3306 (MySQL), I see a suspicious looking web page: Is this exposing any vulnerabilities for me? Should I block port 3306?
9
votes
4answers
14k views

Best place to store authentication tokens client side

When my users are authenticated they receive an authentication token, I need to use this authentication token to authorize some asp.net WebAPI calls. To do this I need to add the token to the head of ...
9
votes
3answers
520 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
1k 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
375 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
votes
4answers
9k views

What is the danger of Reflected Cross Site Scripting?

What is the danger of Reflected Cross Site Scripting? I understand the Reflected XSS is dangerous, because it's possible. But what practical attacks can be performed using Reflected XSS?
9
votes
4answers
6k views

User name enumeration?

From what I understand it is bad security practice to display informative failed login messages like: The email you entered does not exist Instead of Incorrect email/password combination ...
9
votes
3answers
5k 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 ...