Is there a cure for masochism?

No, there is no know cure for masochism.

Masochism isn't a disease, it's a paraphilia, which simply means it's a sexual practise outside the norm. According to the DSM (Diagnostic and Statistical Manual of Mental Disorders), it only requires treatment if it causes you "marked distress or interpersonal difficulty," in which case therapy or counseling might help you figure out how to deal with it better. "Masochistic personality disorder," also known as "Self-defeating personality disorder," is a much more serious problem in which the individual constantly undermines himself and places himself in situations of suffering. It's not an official personality disorder in the DSM, but, if you think this is your problem, you should definitely seek help.
I noticed you placed this category in sexual abuse. If you are asking this because you think that your (or someone else's) masochism is the result of past sexual abuse or causes the person in question to put him/herself in situations leading to sexual abuse, you need to address that. Being a sexual masochist does NOT mean you want to be sexually abused--it means only that you get pleasure from pain and/or humiliation--and anyone engaging in these practices needs to consent and set their own limits.