WordNet (r) 3.0 (2006):

under attack
    adj 1: subjected to enemy attack or censure; "an official under
           fire for mismanagement" [syn: under attack(p), under
           fire(p)]

Moby Thesaurus II by Grady Ward, 1.0:

19 Moby Thesaurus words for "under attack":
   accused, arraigned, blamed, charged, cited, denounced, impeached,
   implicated, impugned, in complicity, incriminated, inculpated,
   indicted, involved, reproached, tasked, taxed, under fire,
   under siege