You would think that above all else, submarine engineers will prevent their subs from leaking.

Apparently the next-generation Indian submarine fleet won’t have that luxury. The Australian reported that 22,400 top secret documents on French contractor DCNS’s construction of Scorpene-class submarines were leaked after the contractor was hacked.

The leaked documents apparently detail some of the most sensitive combat capabilities of India’s soon-to-be six submarine fleet. DCNS, which is partially owned by the government of France, is also contracted to build Scorpene submarines for Malaysia, Chile and Brazil, and is designing Australia’s next submarine fleet.

The hacking of defense contractors has gotten a lot of attention recently, especially in the U.S., with the first federal prosecution for economic cyberespionage coming earlier this year when a Chinese businessman pleaded guilty to conspiracy when he helped two Peoples’ Liberation Army (PLA) hackers steal export-controlled military information.

The prosecution came just two years after the U.S. brought its first indictment for economic cyberespionage against hackers working on behalf of a foreign government when it indicted five PLA officers.

Among the documents leaked are those that describe the submarine stealth capabilities, such as frequency at which the submarines gather intelligence, and their diving depth, range and endurance, and magnetic, electromagnetic and infra-red data.

With access to that kind of stealth data, India’s regional rivals, Pakistan and China, may be waiting for India when it finds the sea of green.

The hacking of the French contractor will also set off alarm bells in the U.S., as the U.S. is supplying Australia’s French-designed Shortfin Barracuda submarine with its latest stealth technology.

Before providing its stealth technology, the U.S. should deliver a screen door to DCNS headquarters and see where it ends up.

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