The most common and most likely answer to this crossword clue is the 8 letter word BOMBARDS
I've seen this crossword clue in The Guardian
B
O
M
B
A
R
D
S
Buddy explains!

The straight part
We know that "attacks" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case attacks = bombards.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 BOMBARDS mean?
BOMBARDS noun- A medieval primitive cannon, used chiefly in sieges for throwing heavy stone balls.
- A bassoon-like medieval instrument
- A large liquor container made of leather, in the form of a jug or a bottle.
- A bombardment.
- A bombardon.
- To continuously attack something with bombs, artillery shells or other missiles or projectiles.
- To attack something or someone by directing objects at them.
- To direct at a substance an intense stream of high-energy particles, usually sub-atomic or made of at most a few atoms.