How do I fix validation ViewState failed MAC?

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Validation of viewstate MAC failed. If this application is hosted by a web farm or cluster, ensure that <machineKey> configuration specifies the same validationKey and validation algorithm. AutoGenerate cannot be used in a cluster.

How do I enable ViewState on MAC?

Solution. ASP.NET provides MAC validation for ViewState parameters by adding ‘<%@Page EnableViewStateMAC=’True’ %>’ on the specific page or by adding ‘<pages enableViewStateMac=’true’>’ inside your web. config file.

What causes invalid ViewState errors?

The error message is caused by some exception being thrown when the view state is being processed. The problem is that the exception is being consumed, and its details are lost in the error message. By using a debugger, you can determine the original exception.

What is message authentication code in network security?

Message Authentication Code (MAC), also referred to as a tag, is used to authenticate the origin and nature of a message. MACs use authentication cryptography to verify the legitimacy of data sent through a network or transferred from one person to another.

What causes MAC validation errors?

A MAC validation error will resemble the following example: Server Error in ‘/’ Application. Validation of viewstate MAC failed. If this application is hosted by a web farm or cluster, ensure that <machineKey> configuration specifies the same validationKey and validation algorithm.

How do I find the machine key in web config?

To do this, please follow these instructions:

Go to IIS console on one of the webservers > Sites > select the Pyramid website > double-click on Machine Key icon in center pane.
In Machine Key dialog, click on Generate Keys and then Apply.
Copy the generated validation and decryption keys to the notepad.

What is ViewState generator?

The ViewState is basically generated by the server and is sent back to the client in the form of a hidden form field “_VIEWSTATE” for “POST” action requests. The client then sends it to the server when the POST action is performed from the web applications.

Is ViewState secure?

The VIEWSTATE is a security risk if it is not encrypted (anyone could modify the VIEWSTATE values and POST to your pages.) If that page can decode the VIEWSTATE then it is not encrypted.

What is EnableViewState in asp net?

Boolean = Page.EnableViewState Page.EnableViewState = Boolean. Returns or sets a Boolean value that indicates whether the Page maintains its view state and that of server controls it contains. The default value of this property is True , which means that the page maintains its view state.

What is .NET Viewstate?

View state is the method that the ASP.NET page framework uses to preserve page and control values between round trips. When the HTML markup for the page is rendered, the current state of the page and values that must be retained during postback are serialized into base64-encoded strings.

What are the two requirements of MAC?

A MAC requires two inputs: a message and a secret key known only to the originator of the message and its intended recipient(s).

Does MAC provide authentication?

MAC algorithm is a symmetric key cryptographic technique to provide message authentication. For establishing MAC process, the sender and receiver share a symmetric key K. Essentially, a MAC is an encrypted checksum generated on the underlying message that is sent along with a message to ensure message authentication.

How do I check if a MAC address is valid?

A valid MAC address must satisfy the following conditions:

It must contain 12 hexadecimal digits.
One way to represent them is to form six pairs of the characters separated with a hyphen (-) or colon(:).
Another way to represent them is to form three groups of four hexadecimal digits separated by dots(.).

What causes Server Error in ‘/’ application?

The “Server error in ‘/’ application” can occur when a file extension does not have permission to run on the server. When exploring a solution to a “Server error in ‘/’ application”, first ensure that you are using the correct file name.

What is machine key used for?

Machine keys are used to transmit torque from a rotating shaft to a gear or sprocket. They can be finished in a variety of shapes, sizes, and materials for just about any application.

What is machine key?

A machine key tightly secures gears, cams, sprockets, pulleys and other parts to the drive shaft in a power transmission and transmits torque from the main shaft to connected parts. A tapered machine key is used for easy assembly and removal.

Where is ViewState data stored?

By default, view state data is stored in the page in a hidden field and is encoded using base64 encoding. In addition, a hash of the view state data is created from the data by using a machine authentication code (MAC) key.

Is ViewState encrypted by default?

ViewState’s not encrypted as default, using base64 encoding. You may want to use viewstate if your page has an action with controls.

How do you know if ViewState is encrypted?

Copy the viewstate value and decode it using https://www.base64decode.org/ If the decoded output contains any cleartext (long number, “Contentplaceholder”) it means the view state is not encrypted. If the decoded output does not contain any cleartext (or cannot even be decoded) it means the view state is encrypted.

Can we disable ViewState?

ViewState can be easily disabled for a particular control by setting EnableViewState property to False. ViewState can be disabled for the whole Page i.e. all controls on the Page by setting the EnableViewState property to False in the @Page Directive.

How do you get values from ViewState?

To store value in session state use the following technique,

int download = (int)ViewState[“Download”];
int like = (int)ViewState[“Like”];
Session[“download”] =download;
Session[“like”] = like;

What are the validation controls?

Validation controls are used to, Implement presentation logic. To validate user input data. Data format, data type and data range is used for validation.

What does MAC stand for?

1. Short for medium access control, or MAC address. Known as a physical address and hardware address whose number is uniquely formatted in hexadecimal format and given to each computer or network device on a computer network.

Which type of function is a MAC?

A Message Authentication Code (MAC) is a hash function that uses a key. A common MAC implementation is Cipher Block Chaining Message Authentication Code (CBC-MAC), which uses the CBC mode of a symmetric block cipher such as DES to create a MAC.

Does MAC provide authentication or confidentiality?

In this model of MAC, sender encrypts the content before sending it through network for confidentiality. Thus this model provides confidentiality as well as authentication.