The most common and most likely answer to this crossword clue is the 11 letter word UNDISCLOSED
I've seen this crossword clue in Financial Times
U
N
D
I
S
C
L
O
S
E
D
Buddy explains!
The straight part
We know that "kept under wraps" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case kept under wraps = undisclosed.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does UNDISCLOSED mean?
UNDISCLOSED adjective- Not disclosed; kept secret.