Kim Yong-joon /Newsis

Just 40 days since her election as president, Park Geun-hye encountered her first stumbling block on Tuesday, when the head of her so-called transition team and chosen prime minister resigned over the kind of scandal that is practically written into the DNA of Korean politicians.

Kim Yong-joon stepped back only five days after his nomination for PM due to a growing uproar over alleged real estate speculation and both his sons' mysterious exemption from military service.

Kim in a statement read by Park's spokesman sought to minimize damage for the president-elect. "I am solely to blame for this," the statement read. "I do not want to worry the public and cause further problems for the president-elect. That's why I made the decision."

The spokesman said Kim decided to resign after meeting with Park earlier in the day.

There had been some concerns about Park's secretive manner of picking top officials, since nobody knows who advises her or what criteria she applies, let alone how nominees are vetted. Even close aides and officials in the transition team say they have no idea.

This is the first time in modern Korean history that a prime ministerial nominee has resigned before the new administration has even been sworn in. Park made no comment herself, and her spokesman said Kim left it to Park whether to retain him as the head of the transition team.

The clock for viable appointments is now ticking. Officials in the transition team admitted the latest blunder stemmed from Park's excessive emphasis on confidentiality, which resulted in a failure to subject Kim to a proper background check.