Story highlights This is the most important leak to date from Edward Snowden, an analyst says

Reports: NSA and GCHQ have cracked much of the encryption protecting online data

The agencies have secret partnerships with technology companies, the reports say

The encryption safeguards data including e-mails, banking systems and medical records

The reports, produced in partnership and published Thursday, are the latest to emerge based on documents leaked by former NSA contractor Edward Snowden to Britain's Guardian newspaper.

According to the reports, the NSA, alongside its UK equivalent, Government Communications Headquarters, better known as GCHQ , has been able to unscramble much of the encoding that protects everything from personal e-mails to banking systems, medical records and Internet chats.

The agencies' methods include the use of supercomputers to crack codes, covert measures to introduce weaknesses into encryption standards and behind-doors collaboration with technology companies and Internet service providers themselves.

"Through these covert partnerships, the agencies have inserted secret vulnerabilities -- known as backdoors or trapdoors -- into commercial encryption software," The Guardian says.

The Guardian cites a 2010 GCHQ memo that it says describes a briefing on NSA accomplishments given to GCHQ employees.

Photos: Sharing secrets: U.S. intelligence leaks Photos: Sharing secrets: U.S. intelligence leaks Sharing secrets: U.S. intelligence leaks – John Walker ran a father and son spy ring, passing classified material to the Soviet Union from 1967 to 1985. Walker was a Navy communication specialist with financial difficulties when he walked into the Soviet Embassy and sold a piece of cyphering equipment. Navy and Defense officials said that Walker enabled the Soviet Union to unscramble military communications and pinpoint the location of U.S. submarines at all times. As part of his plea deal, prosecutors promised leniency for Walker's son Michael Walker, a former Navy seaman. Click through the gallery to see other high-profile leak scandals the United States has seen over the years. Hide Caption 1 of 10 Photos: Sharing secrets: U.S. intelligence leaks Sharing secrets: U.S. intelligence leaks – Military analyst Daniel Ellsberg leaked the 7,000-page Pentagon Papers in 1971. The top-secret documents revealed that senior American leaders, including three presidents, knew the Vietnam War was an unwinnable, tragic quagmire. Further, they showed that the government had lied to Congress and the public about the progress of the war. Ellsberg surrendered to authorities and was charged as a spy. During his trial, the court learned that President Richard Nixon's administration had embarked on a campaign to discredit Ellsberg, illegally wiretapping him and breaking into his psychiatrist's office. All charges against him were dropped. Since then he has lived a relatively quiet life as a respected author and lecturer. Hide Caption 2 of 10 Photos: Sharing secrets: U.S. intelligence leaks Sharing secrets: U.S. intelligence leaks – Jonathan Pollard is a divisive figure in U.S.-Israeli relations. The former U.S. Navy intelligence analyst was caught spying for Israel in 1985 and was sentenced in 1987 to life imprisonment. Previously, the United States and Israel discussed his possible release as part of efforts to save fragile Middle East peace negotiations, according to sources familiar with the talks. On July 28, 2015, Pollard's lawyer announced that the convicted spy had been granted parole and would be released on November 21 -- exactly 30 years after his arrest. Hide Caption 3 of 10 Photos: Sharing secrets: U.S. intelligence leaks Sharing secrets: U.S. intelligence leaks – Wen Ho Lee was a scientist at the Los Alamos Laboratory in New Mexico who was charged with 59 counts of downloading classified information onto computer tapes and passing it to China. Lee eventually agreed to plead guilty to a count of mishandling classified information after prosecutors deemed their case to be too weak. He was released after nine months in solitary confinement. Lee later received a $1.6 million in separate settlements with the government and five news agencies after he sued them, accusing the government of leaking damaging information about him to the media. Hide Caption 4 of 10 Photos: Sharing secrets: U.S. intelligence leaks Sharing secrets: U.S. intelligence leaks – Members of the Bush administration were accused retaliating against Valerie Plame, pictured, by blowing her cover in 2003 as a U.S. intelligence operative, after her husband, former Ambassador Joe Wilson, wrote a series of New York Times op-eds questioning the basis of certain facts the administration used to make the argument to go to war in Iraq. Hide Caption 5 of 10 Photos: Sharing secrets: U.S. intelligence leaks Sharing secrets: U.S. intelligence leaks – In 2007, Lewis "Scooter" Libby, Vice President Dick Cheney's former chief of staff, was convicted on charges related to the leak of the identity of CIA operative Valerie Plame. Libby was convicted of obstruction of justice and perjury in connection with the case. His 30-month sentence was commuted by President George W. Bush. Cheney told a special prosecutor in 2004 that he had no idea who leaked the information. Hide Caption 6 of 10 Photos: Sharing secrets: U.S. intelligence leaks Sharing secrets: U.S. intelligence leaks – Aldrich Ames, a 31-year CIA employee, pleaded guilty to espionage charges in 1994 and was sentenced to life in prison. Ames was a CIA case worker who specialized in Soviet intelligence services and had been passing classified information to the KGB since 1985. U.S. intelligence officials believe that information passed along by Ames led to the arrest and execution of Russian officials they had recruited to spy for them. Hide Caption 7 of 10 Photos: Sharing secrets: U.S. intelligence leaks Sharing secrets: U.S. intelligence leaks – Robert Hanssen pleaded guilty to espionage charges in 2001 in return for the government not seeking the death penalty. Hanssen began spying for the Soviet Union in 1979, three years after going to work for the FBI and prosecutors said he collected $1.4 million for the information he turned over to the Cold War enemy. In 1981, Hanssen's wife caught him with classified documents and convinced him to stop spying, but he started passing secrets to the Soviets again four years later. In 1991, he broke off relations with the KGB, but resumed his espionage career in 1999, this time with the Russian Intelligence Service. He was arrested after making a drop in a Virginia park in 2001. Hide Caption 8 of 10 Photos: Sharing secrets: U.S. intelligence leaks Sharing secrets: U.S. intelligence leaks – Army Pvt. Bradley Manning was convicted July 30 of stealing and disseminating 750,000 pages of classified documents and videos to WikiLeaks, and the counts against him included violations of the Espionage Act. He was found guilty of 20 of the 22 charges but acquitted of the most serious charge -- aiding the enemy. Manning was sentenced to 35 years in military prison in 2013. Hide Caption 9 of 10 Photos: Sharing secrets: U.S. intelligence leaks Sharing secrets: U.S. intelligence leaks – Former intelligence contractor Edward Snowden revealed himself as the leaker of details of U.S. government surveillance programs run by the U.S. National Security Agency to track cell phone calls and monitor the e-mail and Internet traffic of virtually all Americans. Snowden has been granted temporary asylum in Russia after initially fleeing to Hong Kong. He has been charged with three felony counts, including violations of the U.S. Espionage Act, over the leaks. Hide Caption 10 of 10

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"For the past decade, NSA has lead (sic) an aggressive, multi-pronged effort to break widely used Internet encryption technologies," the memo reportedly says. "Vast amounts of encrypted Internet data which have up till now been discarded are now exploitable."

A second memo is quoted as saying that when the British analysts, who often work alongside NSA officers, were first told about the program, "those not already briefed were gobsmacked."

Another document states that GCHQ has been working to find ways into the encrypted data sent via four big Internet firms, Google, Yahoo, Facebook and Microsoft's Hotmail, the reports claim.

GCHQ told CNN it had no comment on The Guardian report.

The reports claim that the NSA worked to develop more covert ways of unscrambling online data after losing a public battle in the 1990s to insert a government "back door" into all programming.

'Foundation of web security'

Computer security expert Mikko Hypponen believes the revelation is the most important leak to date from Snowden.

"It may not have gained as many headlines as some of his other stories, because most people don't understand how crypto systems work. If indeed U.S intelligence does indeed have such a wide range of systems, then I'm surprised," he told CNN.

Crypto encryption is relevant to everyday applications that everyone uses, for example in communications and transactions, he said. "Now we learn that the foundation of web security has been compromised."

Hypponen, the chief research officer for F-Secure, said he believes the NSA and GCHQ had probably cracked the encryption by placing moles in key companies at key locations. "Any major service provider must have sizable amounts of moles from intelligence agencies. Remember that the NSA has 35,000 people working for it," he said.

"The ordinary user should not be worried by these revelations -- it's obvious that intelligence agencies are not interested in hacking financial transactions -- but they should be outraged."

He suggested those outside the United States should be the most concerned.

"How many U.S. politicians use French cloud-services? Almost none. But how many French politicians use U.S. cloud services? All of them," he said. "Remember that 96% of the planet's inhabitants are foreigners to the United States, so it's wrong that the U.S. has a legal right to access foreign communications."

Public concern

The scope of hidden U.S. surveillance programs has been brought to public light through leaks to media outlets by Snowden, who fled the United States and is now in Russia under temporary asylum . He faces espionage charges.

The revelations have led many Americans, according to polls, to harbor skepticism about the NSA programs. They've also generated concern in Congress as well as from privacy groups and libertarians.

Last month, President Barack Obama sought to allay people's unease over the work of the intelligence agency in an interview with CNN "New Day" anchor Chris Cuomo

Obama said he was confident no one at the NSA is "trying to abuse this program or listen in on people's e-mail." The president chalked much of the concern with domestic snooping on changes in technology.

"I think there are legitimate concerns that people have that technology is moving so quick," Obama said. "What I recognize is that we're going to have to continue to improve the safeguards and as technology moves forward, that means that we may be able to build technologies that give people more assurance."