CVE-2025-55248: Microsoft Security Advisory CVE-2025-55248: .NET Information Disclosure Vulnerability
Microsoft is releasing this security advisory to provide information about a vulnerability in .NET 8.0 and .NET 9.0. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability.
A MITM (man in the middle) attacker may prevent use of TLS between client and SMTP server, forcing client to send data over unencrypted connection.
References
- github.com/advisories/GHSA-gwq6-fmvp-qp68
- github.com/dotnet/announcements/issues/372
- github.com/dotnet/runtime
- github.com/dotnet/runtime/issues/120713
- github.com/dotnet/runtime/security/advisories/GHSA-gwq6-fmvp-qp68
- msrc.microsoft.com/update-guide/vulnerability/CVE-2025-55248
- nvd.nist.gov/vuln/detail/CVE-2025-55248
Code Behaviors & Features
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