An elevation of privilege vulnerability exists when a ASP.NET Core web application, created using vulnerable project templates, fails to properly sanitize web requests. An attacker who successfully exploited this vulnerability could perform content injection attacks and run script in the security context of the logged-on user.
To exploit the vulnerability, an attacker could send a specially crafted email, containing a malicious link, to a user. Alternatively, an attacker could use a chat client to social engineer a user into clicking the malicious link. However, in all cases to exploit this vulnerability a user must click a maliciously crafted link from an attacker.
The security update addresses the vulnerability by correcting the ASP.NET Core project templates.