.NET and Visual Studio Elevation of Privilege Vulnerability

Vulnerability

Overview

CVE-2023-33127 is an elevation of privilege vulnerability in .NET and Visual Studio. The flaw resides in the diagnostic server component of .NET applications, which can be exploited to achieve cross-session and cross-user elevation of privilege (EoP) and remote code execution [1][2]. The vulnerability affects .NET 7.0 (versions 7.0.8 and earlier) and .NET 6.0 (versions 6.0.19 and earlier), including specific runtime packages for Windows desktops [1][2].

Exploitation

Details

The vulnerability does not require authentication to exploit, as the diagnostic server is exposed to other users on the same system. An attacker with low privileges on the local machine can leverage the diagnostic server's flaws to execute code in the context of another user or session [1][2]. Microsoft has not identified any mitigating factors for this vulnerability [1][2].

Impact

Successful exploitation allows an attacker to escalate privileges from a low-integrity context to a higher integrity level, potentially leading to full system compromise. The CVSS score is not provided in the references, but the advisory classifies this as an elevation of privilege vulnerability [3].

Mitigation

Microsoft released patches in .NET 7.0.9 and .NET 6.0.20, as well as updated Windows Desktop runtime packages for affected architectures [1][2]. Developers should update their .NET SDKs and runtime installations immediately. The vulnerability is not listed on the CISA Known Exploited Vulnerabilities (KEV) catalog as of July 2023.