In two separate attacks over the past few days, hacker groups threatened to release highly sensitive information unless ransoms were paid.

On March 12, 2015, a hacker demanded an undisclosed sum of money in exchange for not releasing sensitive information on South Korea's nuclear power plants to third parties, The Korea Times reports (h/t SC Magazine).

The same hacker, using a Twitter handle named after the president of a Hawaiian anti-nuclear group, had previously published information on South Korea's nuclear power plants five times, beginning on December 15, 2014,

"Need money. Only need to meet some demands... Many countries from Northern Europe, Southeast Asia and South America are saying they will buy nuclear reactor information," the hacker stated on Twitter. "Fear selling the entire information will undermine President Park's efforts to export nuclear reactors."

Along with the post, the hacker published some new files on Twitter regarding South Korea's APR-1400 reactor, though the Korea Hydro & Nuclear Power Co. (KHNP) stated that the files didn't include any sensitive information, and may have been obtained before the company last year improved its cyber security.

"Since the so-called anti-nuclear group made its fifth release of information on Dec. 23, no cyber attack or information leak has taken place, while the documents released today appear to have been obtained long before," KHNP said in a press release.

Still, according to The Korea Times, one of the files released on March 12 reportedly was a transcript of a phone conversation between South Korean President Park Geun-hye and United Nations Secretary-General Ban Ki-moon on January 1, 2015.

Separately, the hacker group Rex Mundi announced on March 13, 2015 that it had stolen hundreds of blood test results from the French diagnostic laboratory Labio as PDF files (h/t

"We post them Tuesday if Labio doesn't pay," the hackers tweeted.

In a post on dpaste, the hackers published the names of the patients affected and stated, "Last week, we hacked the website of Labio, a French clinical laboratory. From the test results server, we downloaded hundreds of blood test results in addition to all of the 40,000+ stored login credentials."

"We offered Labio not to release their patients' data in exchange for a very reasonable EUR 20,000," the hackers added. "Unfortunately, so far, it seems as if they would rather save a little bit of money rather than protect their patients' privacy."

While Labio hasn't yet published a statement regarding the attack, its website now states that test results are currently not available online "due to a technical problem," and that patients are advised to contact the laboratory directly to request results.

Rex Mundi has made similar demands in the past following attacks on companies ranging from the Belgian Web host Alfanet to Domino's Pizza, but the data they're threatening to release now is far more sensitive than in any of those previous cases.

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