*Sigh* This is a very complicated question that strays into a lot of domains. Mostly, it revolves around chain of command and how closely your company follows it. I've been in a couple of these situations, unfortunately, with differing outcomes. In the one case, I was an incoming lower-level manager, taking over for someone who left suddenly and finding the entire department in disarray. My immediate boss was worse than useless, and I very quickly learned that he took everything I was saying, much of which dealt with either making the shop run more efficiently, or data security, which we had glaring holes in, and just sat on it. So I went around him, to the next person up in the chain, and met the same sort of resistance. Eventually, one of the glaring holes got discovered, and $#!+ hit the fan as it tends to. In the ensuing mess I got called into the office of the person effectively running the company at that point and asked point blank why nothing had been done about the holes. I answered honestly, and as respectfully as possible. The outcome was me being told to do my boss's job, which I did, right up until he retired, at which point I took his job.
By contrast, about two years after that, and some serious leadership shakeups later, I had an issue where we were putting load on a machine that it couldn't handle, enough so that it was bound to fail sooner rather than later. no less than three people, including myself went to my boss, and pointed out, in varying shades of politeness, that it was going to fail, and were brushed off. When it inevitably failed, in a way that was obviously his fault, he punished all three of us in various ways that were difficult to put back on him, until he left the company.
The third time, it happened to me. I was giving a business case for some training I wanted to take some members of my shop to. unbeknownst to my boss, I had gone to our training department and already had them sign off on it, I was just getting my boss to sign as a courtesy. Of course, -I- didn't tell him that. My boss notes that one of my employees had a disciplinary infraction, and sent an email to both of us saying that he couldn't go to any training. Before I could reply, my subordinate fires an email to said boss stating something to the effect of "But the Training Office has already approved it." Ensuing fireworks were spectacular. I got what I wanted, but it sparked an ongoing friction between our HR department and our IT department to this day.
You need to gauge your command climate, and the temperament of your bosses. Even if you can't go around your boss, you can write your business case, and find a way to present it to your boss for his "rewrite". If you do the work for him, often times he'll be willing to do a tiny bit extra in order to get the credit. Does it look as good on you? No. Does it get the job done? Yes.