Overloads Overridable Friend - vb

According to MSDN,

You should never base the security of your application on a member that is

marked with the internal virtual modifier in C# (the Overloads Overridable
Friend modifier in Visual Basic). Although members marked with these
modifiers can only be overridden by other members within the current
assembly, this rule is enforced only by the C# and Visual Basic languages.
The runtime does not enforce this rule. It is therefore possible to override
members marked as internal virtual in C# and Overloads Overridable Friend in
Visual Basic using Microsoft Intermediate Language, or any other language
that does not enforce this rule.
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My question is, can you provide an example of code that overrides members
marked as Overloads Overridable Friend using MSIL or another language that
does not enforce this rule?