蠹 ⇒
蠹 dù, insect that eats into books, clothing etc/moth-eaten/worm-eaten
蠹虫 dùchóng, [蠹蟲], moth/harmful person/vermin
弊 ⇒
作弊 zuòbì, to practice fraud/to cheat/to engage in corrupt practices
弊 bì, detriment/fraud/harm/defeat
利弊 lìbì, pros and cons/merits and drawbacks/advantages and disadvantages
弊端 bìduān, malpractice/abuse/corrupt practice
舞弊 wǔbì, to engage in fraud
弊病 bìbìng, malady/evil/malpractice/drawback/disadvantage
兴利除弊 xīnglìchúbì, [興利除弊], to promote what is useful and get rid of what is harmful (idiom)
徇私舞弊 xùnsīwǔbì, to abuse one's position for personal gain (idiom)