Stuxnet

September 25, 2010
Iran Fights Malware Attacking Computers
By DAVID E. SANGER
WASHINGTON — The Iranian government agency that runs the country’s nuclear facilities, including those the West suspects are part of a weapons program, has reported that its engineers are trying to protect their facilities from a sophisticated computer worm that has infected industrial plants across Iran.

The agency, the Atomic Energy Organization, did not specify whether the worm had already infected any of its nuclear facilities, including Natanz, the underground enrichment site that for several years has been a main target of American and Israeli covert programs.

But the announcement raised suspicions, and new questions, about the origins and target of the worm, Stuxnet, which computer experts say is a far cry from common computer malware that has affected the Internet for years. A worm is a self-replicating malware computer program. A virus is malware that infects its target by attaching itself to programs or documents.

Stuxnet, which was first publicly identified several months ago, is aimed solely at industrial equipment made by Siemens that controls oil pipelines, electric utilities, nuclear facilities and other large industrial sites. While it is not clear that Iran was the main target — the infection has also been reported in Indonesia, Pakistan, India and elsewhere — a disproportionate number of computers inside Iran appear to have been struck, according to reports by computer security monitors.

Given the sophistication of the worm and its aim at specific industrial systems, many experts believe it is most probably the work of a state, rather than independent hackers. The worm is able to attack computers that are disconnected from the Internet, usually to protect them; in those cases an infected USB drive is plugged into a computer. The worm can then spread itself within a computer network, and possibly to other networks.

The semiofficial Mehr news agency in Iran on Saturday quoted Reza Taghipour, a top official of the Ministry of Communications and Information Technology, as saying that “the effect and damage of this spy worm in government systems is not serious” and that it had been “more or less” halted.

But another Iranian official, Mahmud Liai of the Ministry of Industry and Mines, was quoted as saying that 30,000 computers had been affected, and that the worm was “part of the electronic warfare against Iran.”

ISNA, another Iranian news agency, had reported Friday that officials from Iran’s atomic energy agency had been meeting in recent days to discuss how to remove the Stuxnet worm, which exploits some previously unknown weaknesses in Microsoft’s Windows software. Microsoft has said in recent days that it is fixing those vulnerabilities.

It is extraordinarily difficult to trace the source of any sophisticated computer worm, and nearly impossible to determine for certain its target.

But the Iranians have reason to suspect they are high on the target list: in the past, they have found evidence of sabotage of imported equipment, notably power supplies to run the centrifuges that are used to enrich uranium at Natanz. The New York Times reported in 2009 that President George W. Bush had authorized new efforts, including some that were experimental, to undermine electrical systems, computer systems and other networks that serve Iran’s nuclear program, according to current and former American officials.

The program is among the most secret in the United States government, and it has been accelerated since President Obama took office, according to some American officials. Iran’s enrichment program has run into considerable technical difficulties in the past year, but it is not clear whether that is because of the effects of sanctions against the country, poor design for its centrifuges, which it obtained from Pakistan, or sabotage.

“It is easy to look at what we know about Stuxnet and jump to the conclusion that it is of American origin and Iran is the target, but there is no proof of that,” said James Lewis, a senior fellow at the Center for Strategic and International Studies in Washington and one of the country’s leading experts on cyberwar intelligence. “We may not know the real answer for some time.”

Based on what he knows of Stuxnet, Mr. Lewis said, the United States is “one of four or five places that could have done it — the Israelis, the British and the Americans are the prime suspects, then the French and Germans, and you can’t rule out the Russians and the Chinese.”

President Obama has talked extensively about developing better cyberdefenses for the United States, to protect banks, power plants, telecommunications systems and other critical infrastructure. He has said almost nothing about the other side of the cybereffort, billions of dollars spent on offensive capability, much of it based inside the National Security Agency.

The fact that the worm is aimed at Siemens equipment is telling: the company’s control systems are used around the world, but have been spotted in many Iranian facilities, say officials and experts who have toured them. Those include the new Bushehr nuclear power plant, built with Russian help.

But Bushehr is considered by nuclear weapons experts to be virtually no help to Iran in its suspected weapons program; there is more concern about the low-enriched uranium produced at Natanz, which could, with a year or more of additional processing, be converted to bomb fuel.

John Markoff contributed reporting from San Francisco, and William Yong from Tehran.

http://www.nytimes.com/2010/09/26/w...1&partner=rss&emc=rss&src=ig&pagewanted=print

 

In a Computer Worm, a Possible Biblical Clue
By JOHN MARKOFF and DAVID E. SANGER
Deep inside the computer worm that some specialists suspect is aimed at slowing Iran’s race for a nuclear weapon lies what could be a fleeting reference to the Book of Esther, the Old Testament tale in which the Jews pre-empt a Persian plot to destroy them.

That use of the word “Myrtus” — which can be read as an allusion to Esther — to name a file inside the code is one of several murky clues that have emerged as computer experts try to trace the origin and purpose of the rogue Stuxnet program, which seeks out a specific kind of command module for industrial equipment.

Not surprisingly, the Israelis are not saying whether Stuxnet has any connection to the secretive cyberwar unit it has built inside Israel’s intelligence service. Nor is the Obama administration, which while talking about cyberdefenses has also rapidly ramped up a broad covert program, inherited from the Bush administration, to undermine Iran’s nuclear program. In interviews in several countries, experts in both cyberwar and nuclear enrichment technology say the Stuxnet mystery may never be solved.

There are many competing explanations for myrtus, which could simply signify myrtle, a plant important to many cultures in the region. But some security experts see the reference as a signature allusion to Esther, a clear warning in a mounting technological and psychological battle as Israel and its allies try to breach Tehran’s most heavily guarded project. Others doubt the Israelis were involved and say the word could have been inserted as deliberate misinformation, to implicate Israel.

“The Iranians are already paranoid about the fact that some of their scientists have defected and several of their secret nuclear sites have been revealed,” one former intelligence official who still works on Iran issues said recently. “Whatever the origin and purpose of Stuxnet, it ramps up the psychological pressure.”

So a calling card in the code could be part of a mind game, or sloppiness or whimsy from the coders.

The malicious code has appeared in many countries, notably China, India, Indonesia and Iran. But there are tantalizing hints that Iran’s nuclear program was the primary target. Officials in both the United States and Israel have made no secret of the fact that undermining the computer systems that control Iran’s huge enrichment plant at Natanz is a high priority. (The Iranians know it, too: They have never let international inspectors into the control room of the plant, the inspectors report, presumably to keep secret what kind of equipment they are using.)

The fact that Stuxnet appears designed to attack a certain type of Siemens industrial control computer, used widely to manage oil pipelines, electrical power grids and many kinds of nuclear plants, may be telling. Just last year officials in Dubai seized a large shipment of those controllers — known as the Simatic S-7 — after Western intelligence agencies warned that the shipment was bound for Iran and would likely be used in its nuclear program.

“What we were told by many sources,” said Olli Heinonen, who retired last month as the head of inspections at the International Atomic Energy Agency in Vienna, “was that the Iranian nuclear program was acquiring this kind of equipment.”

Also, starting in the summer of 2009, the Iranians began having tremendous difficulty running their centrifuges, the tall, silvery machines that spin at supersonic speed to enrich uranium — and which can explode spectacularly if they become unstable. In New York last week, Iran’s president, Mahmoud Ahmadinejad, shrugged off suggestions that the country was having trouble keeping its enrichment plants going.

Yet something — perhaps the worm or some other form of sabotage, bad parts or a dearth of skilled technicians — is indeed slowing Iran’s advance.

The reports on Iran show a fairly steady drop in the number of centrifuges used to enrich uranium at the main Natanz plant. After reaching a peak of 4,920 machines in May 2009, the numbers declined to 3,772 centrifuges this past August, the most recent reporting period. That is a decline of 23 percent. (At the same time, production of low-enriched uranium has remained fairly constant, indicating the Iranians have learned how to make better use of fewer working machines.)

Computer experts say the first versions of the worm appeared as early as 2009 and that the sophisticated version contained an internal time stamp from January of this year.

These events add up to a mass of suspicions, not proof. Moreover, the difficulty experts have had in figuring out the origin of Stuxnet points to both the appeal and the danger of computer attacks in a new age of cyberwar.

For intelligence agencies they are an almost irresistible weapon, free of fingerprints. Israel has poured huge resources into Unit 8200, its secretive cyberwar operation, and the United States has built its capacity inside the National Security Agency and inside the military, which just opened a Cyber Command.

But the near impossibility of figuring out where they came from makes deterrence a huge problem — and explains why many have warned against the use of cyberweapons. No country, President Obama was warned even before he took office, is more vulnerable to cyberattack than the United States.

For now, it is hard to determine if the worm has infected centrifuge controllers at Natanz. While the S-7 industrial controller is used widely in Iran, and many other countries, even Siemens says it does not know where it is being used. Alexander Machowetz, a spokesman in Germany for Siemens, said the company did no business with Iran’s nuclear program. “It could be that there is equipment,” he said in a telephone interview. “But we never delivered it to Natanz.”

But Siemens industrial controllers are unregulated commodities that are sold and resold all over the world — the controllers intercepted in Dubai traveled through China, according to officials familiar with the seizure.

Ralph Langner, a German computer security consultant who was the first independent expert to assert that the malware had been “weaponized” and designed to attack the Iranian centrifuge array, argues that the Stuxnet worm could have been brought into the Iranian nuclear complex by Russian contractors.

“It would be an absolute no-brainer to leave an infected USB stick near one of these guys,” he said, “and there would be more than a 50 percent chance of having him pick it up and infect his computer.”

There are many reasons to suspect Israel’s involvement in Stuxnet. Intelligence is the single largest section of its military and the unit devoted to signal, electronic and computer network intelligence, known as Unit 8200, is the largest group within intelligence.

Yossi Melman, who covers intelligence for the newspaper Haaretz and is at work on a book about Israeli intelligence over the past decade, said in a telephone interview that he suspected that Israel was involved.

He noted that Meir Dagan, head of Mossad, had his term extended last year partly because he was said to be involved in important projects. He added that in the past year Israeli estimates of when Iran will have a nuclear weapon had been extended to 2014.

“They seem to know something, that they have more time than originally thought,” he said.

Then there is the allusion to myrtus — which may be telling, or may be a red herring.

Several of the teams of computer security researchers who have been dissecting the software found a text string that suggests that the attackers named their project Myrtus. The guava fruit is part of the Myrtus family, and one of the code modules is identified as Guava.

It was Mr. Langner who first noted that Myrtus is an allusion to the Hebrew word for Esther. The Book of Esther tells the story of a Persian plot against the Jews, who attacked their enemies pre-emptively.

“If you read the Bible you can make a guess,” said Mr. Langner, in a telephone interview from Germany on Wednesday.

Carol Newsom, an Old Testament scholar at Emory University, confirmed the linguistic connection between the plant family and the Old Testament figure, noting that Queen Esther’s original name in Hebrew was Hadassah, which is similar to the Hebrew word for myrtle. Perhaps, she said, “someone was making a learned cross-linguistic wordplay.”

But other Israeli experts said they doubted Israel’s involvement. Shai Blitzblau, the technical director and head of the computer warfare laboratory at Maglan, an Israeli company specializing in information security, said he was “convinced that Israel had nothing to do with Stuxnet.”

“We did a complete simulation of it and we sliced the code to its deepest level,” he said. “We have studied its protocols and functionality. Our two main suspects for this are high-level industrial espionage against Siemens and a kind of academic experiment.”

Mr. Blitzblau noted that the worm hit India, Indonesia and Russia before it hit Iran, though the worm has been found disproportionately in Iranian computers. He also noted that the Stuxnet worm has no code that reports back the results of the infection it creates. Presumably, a good intelligence agency would like to trace its work.

Ethan Bronner contributed reporting from Israel, and William J. Broad from New York.

http://www.nytimes.com/2010/09/30/world/middleeast/30worm.html?_r=1&pagewanted=print