The word, seemingly becoming obsolescent, is sneaked, the past tense form of the verb "to sneak."
The poor vulgar colloquialism replacing it is the word snuck, a truly inelegant form that reminds one of other rude words ending in "-uck," with neither present nor past tense form. In the past tense, it ought to at least be expressed as "snucked."
The correct and proper past these of the verb "to sneak" is "sneaked," as mentioned.
Using the word "snuck" marks one as either rude of education, or ignorant of the use of the simplest dictionary for preparing articles fit to be printed, from the language syntax sense.
Let's have the word "sneaked" back again, eh?
No.
'Sneaked' is one of those words that, while technically correct, sounds ugly... though not as bad as pleaded or bleeded.