Security Patched Website Performance Issues (2014.1.403.45)

2 posts, 0 answers
  1. Damien
    Damien avatar
    1 posts
    Member since:
    Oct 2014

    Posted 02 Oct 2020 Link to this post


    A couple of months ago our company were alerted to a Telerik security issue with 2 of the DotNet 4.5 web sites we host / support. We followed the advice and patched the dll and made some amendments in the web.config to prevent AsyncUpload functionality.


    Since the patches were added the performance of both sites (on 2 different Rackspace servers) have slowed up to virtually unusable levels. No other changes have been made to the code or setup of the sites/servers as these are not actively developed due to their age (lost count how many times have we expressed a need to upgrade the sites!).


    Has anyone ever experienced a similar situation or got any ideas what may have caused the issue and how to get functioning sites back?

  2. Attila Antal
    Attila Antal avatar
    591 posts

    Posted 07 Oct 2020 Link to this post

    Hi Damien,

    This is the first time somebody reports performance problems after patching the assemblies and I can't tell what causes it until debugging the app.

    There are a couple of steps you can try to troubleshoot this issue and find out whether Telerik is at fault, if so, which control.

    First, try to remove Telerik controls from the page. If the Site still works slowly, that must be a site configuration problem. However, If the site speeds up, that indicates that Telerik Controls have something to do with the performance and will require attention. Assemblies on their own do no harm if referenced in the project, and the Telerik Controls should be okay unless there is a custom code that makes a time-consuming job, hence decreasing performance.

    If there are multiple Telerik Controls on the page, you can also try removing them one by one. That would help to find out which of the controls is at fault.

    We can investigate the problem, but for that, we would need a sample project that we can run locally or if you could describe the steps that will help us replicate the issue, that would help as well.

    Kind regards,
    Attila Antal
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