OP, Jews are known for making "umbrella rules" to cover all the bases, just in case. A great example of this is the Jewish prohibition of cooking a kid in its own mother's milk. We are a peculiar people who are different, and back then nations which would be classified as pagan did that, therefore we were forbidden. Does this mean we can go do this now? No, not really. We know more about safety cooking practices involving pork, but we still can't eat it (
not even with a fork!). Why do I bring this up? Well, most Jews nowadays forbid the mixing of dairy and meat as an umbrella law, even though the bible never made that mandate. My people, the Sephardi, even went one step further to prohibit cheese with chicken. Yeah, the problem some Jews like me face are these traditional umbrella rules that sometimes make no sense. Take the poor Ashkenazi who can't even eat rice during passover, a prohibition that is nowhere in the bible!
Modern Judaism tends to be the bible, plus tradition. Personally, I think that sometimes with some Jews, the bible itself gets lost in the shuffle, and that is a shame.
That being said, as for the act of masturbation alone, the bible makes
no prohibition on it, male or female. Simple as that. As for Judaism's umbrella rules, they vary greatly. It is important to keep in mind that while masturbation itself isn't prohibited, things that come with it to some people like coveting and lust, are indeed biblically sins. Everyone sins, even the people who wrote these traditional umbrella rules sinned. There's a saying that we must strive to be as great as Moses, but the bible states that no man would be greater than Moses, and that even he was human like everyone else, and he sinned too.
So no, while umbrella rules have been made on the issue otherwise, and Judaism tends to be more than just the bible, our bible does not list masturbation itself as a prohibition.