A configuration management framework, PowerShell provides a command-line shell, and a scripting language for task automation. It is powered by .NET, which uses a text encoding package that has recently been patched against a RCE vulnerability.
As per an update posted on Microsoft Azure’s website, “If you manage your Azure resources from PowerShell version 7.0 or 7.1, we’ve released new versions of PowerShell to address a .NET Core remote code execution vulnerability in versions 7.0 and 7.1. We recommend that you install the updated versions as soon as possible.”
With a score of 9.8, the .NET vulnerability has been identified as a critical vulnerability and was patched in April.
The vulnerability, tracked as CVE-2021-26701 was found in the System.Text.Encodings.Web package and impacts .NET 5.0, .NET Core 3.1, and .NET Core 2.1.
In order to avoid falling prey to the vulnerability, Microsoft is urging users to upgrade from PowerShell v7.0 to 7.0.6. Similarly, users of PowerShell v7.1 should switch to v7.1.3.
Beyond PowerShell, Microsoft’s initial advisory also provides guidance to developers to remove this vulnerability from their .NET-powered apps.
“The vulnerable package is System.Text.Encodings.Web. Upgrading your package and redeploying your app should be sufficient to address this vulnerability,” explained Microsoft.