Illegal online flyers expose search portal gaps

Online leaflet operators, often called web jirashi, are thriving by exploiting loopholes in search portals such as Google and Naver to mass distribute illegal promotional materials, including digital flyers. They claim they can quickly produce virtually any type of advertisement, ranging from forged identification documents and fraudulent insurance claims to prostitution and drug sales, and ensure the content appears at the top of search results. For ordinary users, including teenagers who rely heavily on search engines, this exposes them to harmful and illegal advertising with little effective protection.

Illegal advertisements continue to appear openly on major search sites because they are hosted on legitimate websites. Operators hack bulletin boards on corporate, university and organizational websites or use automated programs to flood publicly accessible message boards, pushing the posts to the top of search results. To evade law enforcement tracking, they are reported to have access to more than 5,000 host sites. Alongside web jirashi, another method known as URL jirashi is spreading, in which large numbers of fake internet addresses are created to attract search engine crawlers and boost visibility. Because this approach does not require posting messages on bulletin boards, operators are said to favor it.

Although web jirashi is a global phenomenon, it is particularly widespread in South Korea’s internet environment. According to an overseas academic paper published in 2024, Korean-language posts accounted for 4.9 percent of the world’s 11.9 million web jirashi cases, exceeding the shares for English at 1.7 percent and Japanese at 1.5 percent. In practice, searches for “forged identification” on major portals produce dozens of advertisements displaying Telegram and KakaoTalk IDs linked to illegal operators. Many drug offenders in South Korea, including teenagers, have said they relied primarily on Google searches to purchase drugs.

Government authorities and platform companies say it is difficult to respond in real time to content spread simultaneously through automated programs. Even so, search portals, as primary gateways to information, must not become gateways to crime. Police and relevant agencies should work together to crack down on those who produce and distribute web jirashi and to swiftly block illegal and harmful advertisements. Platform companies, for their part, should meet their social responsibilities commensurate with their vast influence by deploying advanced technologies, including artificial intelligence, to filter harmful content.