Solved

Can the max length on an asp.net text box control be changed before the page is submitted for postback?

Posted on 2016-09-03
2
63 Views
Last Modified: 2016-09-03
I have an Asp.net web form with several text box controls on it. Each text box control has a limit on the number of characters
that can be entered into each text box. Below is an example where the size is limited to 10 characters of input.
Is it possible for a hacker to change the value for the max length of the text box control? It seems to me that somehow if the hacker
were able to do a view source, and then change the field size by manually changing the html page. That he could do that and then submit the web form.



<asp:TextBox ID="TextBox1" runat="server" MaxLength="10"></asp:TextBox>
0
Comment
Question by:brgdotnet
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
2 Comments
 
LVL 29

Accepted Solution

by:
Olaf Doschke earned 500 total points
ID: 41783173
That's true, a hacker can even submit a POST request without using the html form itself at all, once the inputs and their names are known anything could come over. For that reason a client side javascript validation of input can only be helpful to a normal user but never be trusted to only get valid posted data.

The whole concept of validation is well explained here:
https://msdn.microsoft.com/en-us/library/aa479045.aspx

Bye, Olaf.
0
 
LVL 2

Author Closing Comment

by:brgdotnet
ID: 41783306
Thank you.
0

Featured Post

Enroll in May's Course of the Month

May’s Course of the Month is now available! Experts Exchange’s Premium Members and Team Accounts have access to a complimentary course each month as part of their membership—an extra way to increase training and boost professional development.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Sometimes in DotNetNuke module development you want to swap controls within the same module definition.  In doing this DNN (somewhat annoyingly) swaps the Skin and Container definitions to the default admin selections.  To get around this you need t…
In an ASP.NET application, I faced some technical problems. In this article, I list them out and show the solutions that I found.  I hope it will be useful. Problem: After closing a pop-up window, the parent page should be refreshed automaticall…
A short tutorial showing how to set up an email signature in Outlook on the Web (previously known as OWA). For free email signatures designs, visit https://www.mail-signatures.com/articles/signature-templates/?sts=6651 If you want to manage em…
Are you ready to implement Active Directory best practices without reading 300+ pages? You're in luck. In this webinar hosted by Skyport Systems, you gain insight into Microsoft's latest comprehensive guide, with tips on the best and easiest way…

751 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question