Just as security experts match wits with hackers, those trying to block unwanted e-mail face increasingly elaborate “attacks” from spammers trying to slip messages through antispam defenses. “These guys’ technical ability should be respected,” John Graham-Cumming, author of open-source spam filtering software POPFile, told a conference at MIT today. Graham-Cumming outlined several ways spam authors try to evade blocking software, ranging from the simple to the sophisticated. Some messages just alter words to foil basic efforts to spot red-flag words; for example, most recipients know what “Vi*gra,” V1agra” or “V i a g r a” mean, but basic word-blocking software might not. Other efforts involving HTML-coded messages instead of plain text are far more clever. Full Story