You are welcome, Jeffrey! Let me know if you have any other questions! I will be glad to assist you.

 

Regards,
Rumen
Progress Telerik

Hi Jeff,

I'm following up to confirm that we've successfully reproduced the Uncaught TypeError: Cannot read properties of null (reading 'className') issue and have provided a workaround for it.

Regards,
Rumen
Progress Telerik

Hi Jeff,

Thank you for the follow-up!

I attempted to replicate the new error but was unable to reproduce it. Could you please confirm whether the issue occurs in the live demos that run the latest version?

: https://demos.telerik.com/aspnet-ajax/dateinput/overview/defaultcs.aspx? 

To help us investigate further, could you please provide the following details:

• Disable AJAX: Set EnableAJAX="false" in the RadAjaxManager or RadAjaxPanel, then check the browser console for any JavaScript errors. This will help us get more descriptive error messages, as explained: Get more descriptive errors by disabling AJAX.
• Enable the CDN: This can help identify the specific file where the issue is occurring:
  
  

  <telerik:RadScriptManager 
  	ID="RadScriptManager1"    
  	runat="server"    
  	CdnSettings-TelerikCdn="Enabled">
  </telerik:RadScriptManager>

• Isolated Sample: If possible, isolate the issue in a simple, runnable project and share it with us for further examination.

Looking forward to your response.

Regards,
Rumen
Progress Telerik

Hi Jeff,

Thank you for reaching out.

The 2025 Q2 release of Telerik UI for ASP.NET AJAX is scheduled for Wednesday, May 21, and it will include the fix for the Date Picker issue introduced in version 2025.1.416.

In the meantime, to avoid the vulnerability in earlier versions, we recommend applying one of the mitigation options 2 or 3 outlined in our official Knowledge Base article:

• Unsafe Reflection Mitigations (CVE-2025-3600)

These options provide a level of protection and will secure your application until the Q2 update is available.

Regards,
Rumen
Progress Telerik

Hi Patrice,

Thank you for reporting this issue.

We have verified the problem and made your bug report public so others can stay informed about its status.

We identified that the RadDateInputScript.js file has been incorrectly encoded since version 2025.1.218, as a side effect of recent updates to our build infrastructure. We are actively investigating a fix.

In the meantime, could you please try configuring the control to load its embedded scripts or use scripts from a CDN as a workaround? An alternative approach is to obtain RadDateInputScript.js  from the 2024_4_1114 installation -> Telerik_UI_for_ASP.NET_AJAX_2024_4_1114_Dev_hotfix.zip\Scripts\Input\DateInput and to replace the broken file.

 

As a small note of gratitude for reporting the issue, I have updated your Telerik points.

Regards,
Rumen
Progress Telerik

Hi Patrice ,

The error you're encountering, Invalid regular expression: Range out of order in character class, indicates that there is a problem with the syntax of the regular expression used in your JavaScript code. This typically occurs when character ranges within the regular expression are not correctly ordered or overlap incorrectly.

To resolve this issue, here are a few steps you can take:

1. Review the Regular Expression: Examine the character class within the regular expression to ensure that all ranges are correctly ordered. For example, ensure that the start and end characters of each range are properly defined and in the correct order.

2. Simplify the Expression: If the regular expression is complex or includes many ranges, try breaking it down into simpler parts or removing unnecessary ranges. This can help isolate the problematic part of the expression.

3. Use Character Classes Carefully: Ensure that any special characters or Unicode ranges are correctly specified and do not overlap. If you're using Unicode ranges, ensure they are valid and correctly formatted.

4. Validate the Regular Expression: Utilize tools like regex testers available online to validate and test your regular expression independently. This can help identify syntax issues or misconfigurations.

If these suggestions do not help you out, please share additional details, such as the code used for the DateInput and steps to reproduce the error.

Regards,
Vasko
Progress Telerik