Spammers doubled junk mail from Gmail accounts last month and all but iced a touted spam-blocker, PC World reports. Gmail junk rose from 1.3% to 2.6% of all spam in February, overwhelming the company's CAPTCHA programs with spam from multiple accounts. "It's only a matter of time before (CAPTCHAs) are comprehensively defeated," one analyst said.
Gmail's CAPTCHA programs, which try to tell human emailers from machines, stopped 80% of the junk mail but were swamped by spam from two hosts, according to one security vendor. Almost nine in 10 junk emails come from Yahoo's free accounts, but businesses are unwilling to snub messages from such free email domains because they have legitimate uses.