Microsoft PowerShellGet 2.2.5 WDAC access control

Summaryinfo

A vulnerability marked as problematic has been reported in Microsoft PowerShellGet 2.2.5. This affects an unknown function of the component WDAC. Performing a manipulation results in access control. This vulnerability is identified as CVE-2020-16886. The attack can be initiated remotely. There is not any exploit available. Applying a patch is the recommended action to fix this issue.

Detailsinfo

A vulnerability classified as problematic has been found in Microsoft PowerShellGet 2.2.5. This affects an unknown code of the component WDAC. The manipulation with an unknown input leads to a access control vulnerability. CWE is classifying the issue as CWE-284. The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

<p>A security feature bypass vulnerability exists in the PowerShellGet V2 module. An attacker who successfully exploited this vulnerability could bypass WDAC (Windows Defender Application Control) policy and execute arbitrary code on a policy locked-down machine.</p> <p>An attacker must have administrator privileges to create a configuration that includes installing PowerShellGet V2 module onto a machine from the PowerShell Gallery. The WDAC policy must be configured to allow the module to run. After this is done, PowerShell script can be injected and run fully trusted, allowing the attacker arbitrary code execution on the machine.</p> <p>The update addresses the vulnerability by changing how URLs are processed.</p>

The weakness was released 10/13/2020 as confirmed security guidance (Website). The advisory is shared at portal.msrc.microsoft.com. This vulnerability is uniquely identified as CVE-2020-16886. The exploitability is told to be easy. It is possible to initiate the attack remotely. The exploitation needs additional levels of successful authentication. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1068 for this issue. The advisory points out:

A security feature bypass vulnerability exists in the PowerShellGet V2 module. An attacker who successfully exploited this vulnerability could bypass WDAC (Windows Defender Application Control) policy and execute arbitrary code on a policy locked-down machine. An attacker must have administrator privileges to create a configuration that includes installing PowerShellGet V2 module onto a machine from the PowerShell Gallery. The WDAC policy must be configured to allow the module to run. After this is done, PowerShell script can be injected and run fully trusted, allowing the attacker arbitrary code execution on the machine. The update addresses the vulnerability by changing how URLs are processed.

It is declared as proof-of-concept.

Applying a patch is able to eliminate this problem. A possible mitigation has been published immediately after the disclosure of the vulnerability.

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Vendor

• Microsoft

Name

• PowerShellGet

Version

• 2.2.5

License

• commercial

Website

• Vendor: https://www.microsoft.com/

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CPE 2.2info

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If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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