MethodHandles.Lookup::bind allows to create a method handle for an inherited protected member bound to an instance of a parent class.
That's forbidden by the protected access rules. JVMS 4.9.2 says: "If invokevirtual or invokespecial is used to access a protected method declared in a superclass that is a member of a different run-time package than the current class, then the type of the class instance being accessed must be the same as or a subclass of the current class."
Other Lookup factories take that into account by restricting the receiver type (e.g. see the findVirtual + bindTo throwing CCE in the example)

Example:
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public class B extends A {
    public static void main(String[] args) throws Throwable {
        // prints "B", as expected
        MethodHandle bound = lookup().bind(new B() , "m", MethodType.methodType(void.class));
        bound.invoke();

        // prints "A", but should've thrown an exception (IAE or CCE?)
        MethodHandle bound2 = lookup().bind(new A() , "m", MethodType.methodType(void.class));
        bound2.invoke();

        // throws CCE
        lookup().findVirtual(A.class, "m", MethodType.methodType(void.class))
                .bindTo(new A());
    }
}

package pkg;
public class A {
    protected void m() {
        System.out.println(this.getClass().getSimpleName());
    }
}
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