PhantomJS and security hardening

Abstract

Use PhantomJS to generate screenshots of pages that you can use in the Sitecore UI and in emails.

Sitecore uses PhantomJS to generate screenshots of pages that you can use in for example email messages.

PhantomJS is an external executable (.exe) file that is shipped with Sitecore in the $(dataFolder)\tools\phantomjs folder. Sitecore references this file through a setting named ContentTesting.PhantomJS.ExecutablePath in the App_Config\Include\ContentTesting\Sitecore.ContentTesting.config configuration patch file.

Note

To limit access to the PhantomJS executable file, you should place the data folder outside the webroot folder.

The Windows process that Sitecore runs under requires the Read & execute permission on the executable file. The process also requires Read access to the folder itself to access the other files within the folder.

Because PhantomJS is executed from within Sitecore, it runs with the same permissions that have been set for the process that Sitecore is running under. You should run Sitecore with least privilege – only allow access to files and folders that Sitecore needs access to.

Sitecore passes PhantomJS a script that is generated from the RenderScripts processor in the getScreenShotForURL pipeline. This script instructs PhantomJS to write generated images to a specific folder. The GenerateFilename processor is responsible for generating the path and file name for use in the script.

By default, the output path is $(webroot)\temp\screenshots. The process that Sitecore runs under should already have Read and Write permissions to the temp folder. The output folder location is determined within the pipeline, which you can modify to output the files to a different location.

Note

If the folder that is used for the screenshot files has been changed, you can check the pipeline for the new location.

Increase security on content delivery servers

Because screenshots are used in the UI and emails, it is not necessary to generate them on content delivery servers.

To increase security on the content delivery servers:

  • Remove the $(dataFolder)\tools\phantomjs folder including the phantomjs.exe executable file.

  • Disable the getScreenShotForUrl pipeline that launches the PhantomJS process.

    To disable the getScreenshotForUrl pipeline, create a patch file that disables it in the Sitecore.ContentTesting.config configuration file.