ASP.NET and .NET Elevation of Privilege Vulnerability

CVE-2020-1476
Security Vulnerability

Released: Aug 11, 2020

Assigning CNA
Microsoft
CVE.org link
CVE-2020-1476
Impact
Elevation of Privilege
Max Severity
Important

Executive Summary

An elevation of privilege vulnerability exists when ASP.NET or .NET web applications running on IIS improperly allow access to cached files. An attacker who successfully exploited this vulnerability could gain access to restricted files.

To exploit this vulnerability, an attacker would need to send a specially crafted request to an affected server.

The update addresses the vulnerability by changing how ASP.NET and .NET handle requests.

Exploitability

The following table provides an exploitability assessment for this vulnerability at the time of original publication.

Publicly disclosed
No
Exploited
No
Exploitability assessment
Exploitation Less Likely

FAQ

I am running Windows Server 2008, Windows 7, or Windows Server 2008 R2 and I cannot install the Monthly Rollup or Security Only updates for any of the 4.X versions of Microsoft .NET Framework. How do I protect my system from this vulnerability?

There is a known issue with the Monthly Rollup and Security Only updates for the 4.X versions of .NET Framework installed on Windows Server 2008, Windows 7, and Windows Server 2008 R2. For a workaround to this known issue, please see the Article listed in the Security Updates table for the version of .NET Framework you are trying to install.

Acknowledgements

  • Pham Van Khanh (@rskvp93) from Viettel Cyber Security
Microsoft recognizes the efforts of those in the security community who help us protect customers through coordinated vulnerability disclosure. See Acknowledgements for more information.

Security Updates

To determine the support lifecycle for your software, see the Microsoft Support Lifecycle.

Release date Descending
All results loaded
Loaded all 89 rows

Disclaimer

The information provided in the Microsoft Knowledge Base is provided "as is" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.

Revisions

How satisfied are you with the MSRC Security Update Guide?