GHSA-74JP-VM22-8Q8X Microsoft Security Advisory CVE-2026-50659 – .NET Spoofing Vulnerability

Executive summary Microsoft is releasing this security advisory to provide information about a vulnerability in .NET SMTP client System.Net.Mail. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability. A spoofing vulnerability exis...

Inadequate Encryption Strength

Overview Affected versions of this package are vulnerable to Inadequate Encryption Strength via the SMTP process. An attacker can intercept sensitive information by performing a man-in-the-middle attack that prevents the use of TLS, causing data to be sent over an unencrypted connection...

Denial of Service (DoS)

Overview Affected versions of this package are vulnerable to Denial of Service DoS when creating HTTPS web requests while building X509 certificate chains. Details Denial of Service DoS describes a family of attacks, all aimed at making a system inaccessible to its intended and legitimate users...