A lot of socialist dictatorships had arise in the past century. They were the most brutal and careless about human rights.
But go to read Karl Mark, does he say that dictatorship is the way to go? Does he say that a state should enslave dissidents into gulags?
Socialism just advocates the equal distribution of goods, that's all. If someone tells you that we can't equally distribute the good otherwise we'll end up being in a dictatorship, he's either a billionaire or an ignorant. In the past socialism has always been defamed in a dishonest way by the media, specially in western countries.
Socialism upholds basic human rights by insuring that everyone's basic needs are met through equal distribution of government controlled products. Unlike a capitalistic society, which focuses much more on what people want to attain, but don't necessarily need and in that way is a very individualistic, self preserving concept, a socialistic society keeps the focus on the well being and benefits of society as a whole by insuring that as many people as possible receive food, shelter, clothing, and the benefits of government social programs.
Socialism is not founded on a philosophy of natural rights, but on a theory of social betterment. It is not based on an understanding of the natural condition of man and his inherent nature, but on a utopian concept which defines an ideal good. It does not leave to the individual the determination of what constitutes the pursuit of happiness, but decides and dictates this to all members of society. This is a fundamental difference, based on the abstract idealism of socialist theory, as opposed to the realistic view of existence posed by natural rights. (It is treated more fully under the essay on Natural Rights.) While recognizing that all men are created equal in their entitlement to political rights, natural rights also grants to men the freedom to discover their own potential and to make of their life what they will. Natural rights do not attempt to compensate a person for his natural shortcomings, nor diminish the rewards to a person for his natural abilities.
Socialism as well as any other form of government is run by political leaders who abuse authority to their own advantage. Under socialism there is no incentive for the people to be productive as they expect the government to supply everything for their survival. This is evidenced by our socialized system today. Most people on the welfare system (socialized dependence) will not look for any type of productive existence. All become the slaves of the government leadership. While they live in luxury the rest of the people live a life of poverty.
No, socialism does not uphold all of the important human rights, because socialism can only spread misery. The government cannot create wealth, it can only redistribute what already exists. Socialism tries to make everyone equal, but all it does is create disincentives for hard work that result in lowering everyone's standard of living.