It's not the editor that's corrupt (7)
I believe the answer is:
tainted
'that's corrupt' is the definition.
(synonyms)
'it's not the editor' is the wordplay.
'it's not' becomes 'tain' (I can't explain this - if you can you should believe this answer much more).
'the' becomes 't' (the is pronounced as a 't' sound in some dialects).
'editor' becomes 'ed' (abbreviation).
'tain'+'t'+'ed'='TAINTED'
Can you help me to learn more?
(Other definitions for tainted that I've seen before include "Corrupted, sullied" , "Flawed, contaminated" , "corrupt" , "Adulterated" , "Contaminated, polluted" .)