From The Collaborative International Dictionary of English v.0.48 :
Corruptness \Cor*rupt"ness\, n.
The quality of being corrupt.
[1913 Webster]
From WordNet (r) 3.0 (2006) :
corruptness
n 1: the state of being corrupt
2: lack of integrity or honesty (especially susceptibility to
bribery); use of a position of trust for dishonest gain [syn:
corruptness, corruption] [ant: incorruption,
incorruptness]