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MD5Cng Class

Provides a CNG (Cryptography Next Generation) implementation of the MD5 (Message Digest 5) 128-bit hashing algorithm.

Namespace:  System.Security.Cryptography
Assembly:  System.Core (in System.Core.dll)

[HostProtectionAttribute(SecurityAction.LinkDemand, MayLeakOnAbort = true)]
public sealed class MD5Cng : MD5


The HostProtectionAttribute attribute applied to this type or member has the following Resources property value: MayLeakOnAbort. The HostProtectionAttribute does not affect desktop applications (which are typically started by double-clicking an icon, typing a command, or entering a URL in a browser). For more information, see the HostProtectionAttribute class or SQL Server Programming and Host Protection Attributes.

This algorithm is for hashing only and does not provide any encryption or decryption. It uses the BCrypt (BestCrypt) layer CNG.


Using this algorithm with the FIPS Windows security setting enabled throws a CryptographicException.

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Windows 7, Windows Vista, Windows Server 2008 R2, Windows Server 2008

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5