Full disclosure is the only responsible sort of disclosure.
Apple, like Microsoft, has the tendency to sweep things under the rug when they feel it is unlikely the situation will become public. The only way to correct this behavior is release what you find to the public and as fast as possible.
TL:DR of above link: "[responsible disclosure] is like full disclosure, with the addition that all stakeholders agree to allow a period of time for the vulnerability to be patched before publishing the details"
Apple, like Microsoft, has the tendency to sweep things under the rug when they feel it is unlikely the situation will become public. The only way to correct this behavior is release what you find to the public and as fast as possible.