Hmm, I think leaks/scandals are no different from watching porn, and as other have mentioned, some women consider that as cheating already, others don't. In my opinion, cheating isn't just confined to having sex with other women aside from your partner. I think cheating happens when you disrespect the expectations your partner has. For example, if your partner doesn't want you watching porn, and you love your partner, then you respect that expectation and refrain from watching porn. But if, say, you have an open relationship wherein your partner is ok with you having sex with other women with the condition that she always knows what's happening and with whom, then having sex with other women would still not count as cheating because your partner is ok with it.
Tl;dr, cheating for me is knowing exactly what your partner expects from you and intentionally going against it.