China Hacked Japan’s Military Networks

The NSA discovered the intrusion in 2020—we don’t know how—and alerted the Japanese. The Washington Post has the story:

The hackers had deep, persistent access and appeared to be after anything they could get their hands on—plans, capabilities, assessments of military shortcomings, according to three former senior U.S. officials, who were among a dozen current and former U.S. and Japanese officials interviewed, who spoke on the condition of anonymity because of the matter’s sensitivity.


The 2020 penetration was so disturbing that Gen. Paul Nakasone, the head of the NSA and U.S. Cyber Command, and Matthew Pottinger, who was White House deputy national security adviser at the time, raced to Tokyo. They briefed the defense minister, who was so concerned that he arranged for them to alert the prime minister himself.

Beijing, they told the Japanese officials, had breached Tokyo’s defense networks, making it one of the most damaging hacks in that country’s modern history.

More analysis.

Posted on August 14, 2023 at 7:02 AM20 Comments


John Hawkinson August 14, 2023 8:24 AM

When I read this coverage initially, a week ago, I had the same question I have now: presumably when the US and Japan discovered this penetration three years ago, they took action to use it to their advantage as much as possible, i.e. by making wrong or misleading information available through those same channels.

What, if anything, can we reason about that kind of strategy, given that it is both obvious and not mentioned in Ellen Nakashima’s original article, which does not appear to have had any followups?

Does the fact that this was kept under wraps since 2020 and is now public (through a coordinated leak? “three former senior U.S. officials.”) suggest anything? Does it suggest anything different that other intergovernmental hacking incidents have been publicized on far shorter timeframes?

Peter August 14, 2023 8:56 AM

Big FUD as coming up a new budget formulation cycle. Japan, like every nation, has an air gapped defense network for anything of import ala JWICS equiv and I have serious doubts that got hacked, at least in reference to this story.

Always question “the sky is falling” anytime during budget season.

Ted August 14, 2023 8:57 AM

I just want to note that Ellen Nakashima mentioned a book in her article that looks interesting.

I’m guessing it’s “Special Duty: A History of the Japanese Intelligence Community.”

I’m not 100% certain this is the right book though, as the reference was to a Richard Samuels’ history that was “published last year.” The book above was published in 2019. Perhaps she started the article earlier and set it aside? The editorial reviews look intriguing.

Chris Becke August 14, 2023 9:04 AM

Presumably the Americans knew about this because they, too, had hacked the Japanese.

Fazal Majid August 14, 2023 9:52 AM

I find the idea of a Japanese-American general like Paul Nakasone (who shares a surname with a former Japanese Prime Minister, no less) briefing the Japanese quite amusing.

yet another bruce August 14, 2023 10:21 AM

@Chris Becke

Presumably the Americans knew about this because they, too, had hacked the Japanese.

I expect it is easier to get wind of this kind of thing from within the attacking organization.

Trey August 14, 2023 11:06 AM

@ Peter,

an air gapped defense network for anything of import … and I have serious doubts that got hacked

Why, and what would “hacked” even mean in this context? We’ve seen that a tiny USB flash drive or a series of discs is all one needs for an insider to walk out with “all the data”. Is that a hack? Whether the Chinese government is directly “on” the network hardly matters if they’ve got moles who are. I’m sure they can pay quite well, and offer asylum in China for anyone who can make it there (or just to an embassy; sure, countries will fuck with the diplomatic flights of Bolivia, but China would never stand for that).

Unless the air gaps are exceptionally strict, someone who gets clever malware onto an air-gapped network could even have data flowing “across” the gaps automatically. Realistically, military people will want to be e-mailing and phoning each other even for things of moderate import. While the plans to invade China won’t be e-mailed, they’re not gonna have people fly from base to base for all lesser communication.

AL August 14, 2023 11:55 AM

who spoke on the condition of anonymity
So, in other words, this could be total fiction, but it does fill the requirement of the Washington Post to come up with their daily big bad China story.

Clive Robinson August 14, 2023 2:53 PM

@ Chris Becke,

Re : NSA in China’s back lot.

“Presumably the Americans knew about this because they, too, had hacked the Japanese.”

A few days ago apparantly Paul Nakasone who serves as both Director of Cyber Command and as Director of the National Security Agency said that China’s cyber and surveillance capabilities are not ahead of, or even comparable to, to those of the United States.

However he also said,

“There is a scope-scale sophistication that we ascribe to what China is doing today. Are they getting better? Yes,”

“It is the generational challenge that we will address, our children will address, our grandchildren are going to address. We see it across the major lines of national power. And they’re diplomatic, information, military, and economic,”

“It’s different than adversaries that I’ve seen in my three decades-plus of service in the Army.””

So I’m guessing, your guess is closer to the mark than some might suspect.

lurker August 14, 2023 5:24 PM

… cyber security [became] national security. That’s a big year[2021]. And I think that that, from that year forward, we think differently.”

One has to ask, what were they thinking before? Surely if all your supply chains and a big chunk of the military depend on a single fragile and vulnerable system and software suite, then cyber security must be national security, always.

Ismar August 15, 2023 5:28 AM

“ Since then, under American scrutiny, the Japanese have announced they are ramping up network security, boosting the cybersecurity budget tenfold over the next five years and increasing their military cybersecurity force fourfold to 4,000 people”

Sounds like a great business model as I was wandering as to
how long for are the new measures going to hold the intrusions off ?

Givon Zirkind August 15, 2023 6:56 AM

Since the Pentagon has also been compromised at times; I have to wonder if the hack into the Japanese military wasn’t tunneled through the US military networks. After all, when one feels secure, one drops one’s guard. Big mistake.

ResearcherZero August 16, 2023 1:21 AM

There are many ways to get inside access to a network. Not everyone that you have to work with are as brilliant as you would like them to be. Usually there is not an accompanying script from Hollywood.

McGonigal was assigned at one point to the Russian Illegals Program.

“I want to thank the Good Lord for making me a F.B.I. Agent.”



less than helpful… (unless of course you might want an investigation to go nowhere)


see you next Tuesday…

ResearcherZero August 16, 2023 2:03 AM

Hey, they are trying to steal your missile plans, again.

May 20, 2020

“the ministry suspects hackers stole performance requirements that were sent to several defence industry companies as part of the bidding process for the project”

Data likely stolen in the hack, which Mitsubishi disclosed earlier this year, included specifications of hypersonic missile prototypes that Japan is developing,


And from Sep 19, 2011


An elite group of North Korean hackers secretly breached computer networks at a major Russian missile developer for at least five months last year…

The targeted company, commonly known as NPO Mash, has acted as a pioneer developer of hypersonic missiles, satellite technologies and newer-generation ballistic armaments, according to missile experts.


vas pup August 16, 2023 5:04 PM

Why didn’t the Nazis beat Oppenheimer to the nuclear bomb?

“In 1938, two German chemists, Otto Hahn and Fritz Strassmann, discovered nuclear fission. Fission is the reaction in which the nucleus of an atom splits into two or more smaller nuclei, releasing huge amounts of energy.

Harness this power, physicists said, and you could create a bomb so powerful it could flatten entire cities.

Almost immediately, German scientists commenced work on an atomic bomb project. Backed by a strong German industrial base and military interest, the Uranverein (uranium club) employed some of the world’s top nuclear experts.

The US response was The Manhattan Project. Led by J. Robert Oppenheimer, the program began in summer 1942, researching ways to build a fission bomb using the elements uranium and plutonium.

With huge financial backing, it took just three years for Oppenheimer and his team to successfully test their first nuclear weapon. The first “live fire” nuclear weapon hit Hiroshima three weeks later.

By the time The Manhattan Project was up and running, the German nuclear weapons program was already dead. The German researchers knew they would be unable to separate the isotopes necessary for creating an atomic bomb in less than five years. They never achieved a successful chain reaction and had no method of enriching uranium.

The nuclear weapons program was scrapped in July 1942, with the research splitting into nine different institutes around Germany.

“Before 1942 it was a military project, but then it became only a civil project,” Melber told DW.

From then on, the goal shifted away from a nuclear weapon to building a nuclear reactor that could sustain nuclear fission on a smaller scale. Heisenberg moved his research to a cave laboratory under a castle in Haigerloch, Germany, where he and his team built an experimental nuclear reactor comprised of uranium cubes dangling from wire and submerged in a tank of heavy water.

This experiment was the furthest the German nuclear program progressed, but the reactor never worked — there wasn’t enough uranium present in the reactor’s core to achieve a chain reaction. But they were close. Scientists now believe that if the reactors had contained 50% more uranium, Heisenberg could have created the first nuclear reactor.

!!!why did Germany fail to develop its nuclear program?

=>For one, Germany was bleeding scientists. Many Jewish and Polish scientists like Lise Meitner, a Jewish physicist who played an instrumental role in Hahn and Strassmann’s discovery of nuclear fission, fled persecution. A number of these refugees fled to the UK and US, where they worked on the Manhattan Project.

+>Wartime pressure in Germany also rendered scarce some of the resources necessary for the research, like sufficient amounts of enriched uranium, said Melber. Water, which is needed to cool nuclear reactors, was also in short supply.

“Heavy water production was underway in Nazi-occupied Norway, but Allied and Norwegian forces attacked these facilities,” said Melber.

=>But ultimately it was the lack of political support that halted progress.

“Hitler had difficulties understanding the project” and cut support of it in 1942, Melber said. Without this backing, the nuclear program had very few resources to draw on, especially compared to the US Manhattan Project, which !!!!employed 500,000 people, about 1% of the US workforce, and !!!!cost the US government around $2 billion (today around $24 billion, or €22 billion).

By comparison, the Uranverein and subsequent programs involved !!!!!fewer than a thousand scientists and were budgeted at !!!8 million reichsmarks, equivalent to about $24 million dollars today.

=>another reason for the German failure — the scientists themselves were morally opposed to the atomic bomb and secretly sabotaged the effort.

!!!Eighty years on, the irony is that the modern German state hosts US nuclear weapons, believing them vital for Germany’s security, but is vehemently opposed to nuclear power.”

Clive Robinson August 16, 2023 5:57 PM

@ vas pup, ALL,

Re : WWII fission.

“Why didn’t the Nazis beat Oppenheimer to the nuclear bomb?”

The answer is a little more prosaic than that.

If the Germans had tried to make the process to enrich Uranium into isotopes by “mass” they would have run into the same problem the US did which was the amount of land required to build the fascilities to do it.

The US industry did not have to worry about “air raids” where as the Germans did.

One of the only reasons the V2 went ahead was it prommised Hittler a way to bomb the US from Germany.

Which is where cryptography comes into the argument.

The Germans were “running out of time” their V-weapons development was being slowed to a crawl because the production was found and bombed into holes in the ground. Even when built deep underground or underneath mountains the Barns Wallis “Earthquake bomb” destroyed the production.

Every time the German’s moved production it was found by,

1, Traffic Analysis
2, Enigma and other cipher breaking
3, Intelligence reports from resistance fighters.

And later very effective and highly accurate,

4, Aerial reconnaissance
5, Pathfinding precission targeting

So almost before the Germans could get V-Weapon production facilities ready they got bombed.

I can not remember where they are online, but the Germans were excellent records keepers and you can see time lines of this aspect of the war (when I last used the records I got access to them through the “Imperial War Museum” in London).

Yosemite Sam August 21, 2023 7:27 PM

With viruses inserted in software
Plus Trojans embedded in hardware
Add high technology made in China
And hacking takes place everywhere.

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