Microsoft claims it addressed Windows exploits, released last week in a Shadow Brokers dump, in patches ahead of the leak.

Last Friday the Shadow Brokers released a series of Windows exploits allegedly belonging to the National Security Agency (NSA). Months ago, the group attempted to sell a database of Windows exploits, but quit after failing to secure buyers.

Its latest dump includes code indicating the NSA may have accessed the SWIFT interbank system, which would have enabled it to spy on messaging activity among global banks. At the time of the leak, many reports suggested Windows operating systems could be vulnerable to attack.

In a blog post published April 14, Microsoft reports it looked into the exploits disclosed by Shadow Brokers and discovered most of them had already been addressed in March updates.

"Customers have expressed concerns around the risk this disclosure potentially creates," wrote Phillip Misner of the Microsoft Security Response Center (MSRC). "Our engineers have investigated the disclosed exploits, and most of the exploits are already patched."

The three exploits not addressed in the patch cannot be reproduced on supported systems, meaning users running Windows 7 and above, or Exchange 2010 and above, are not at risk. Those using earlier versions of either are advised to upgrade.

Microsoft has not disclosed how it became aware of the vulnerability. The company claims it was not contacted by the government with information about the exploits.

"Other than reporters, no individual or organization has contacted us in relation to the materials released by Shadow Brokers," it reported to Reuters.

It's worth noting that the NSA knew about the Shadow Brokers breach for months, the report continues. As per a government process created by staff of President Barack Obama, companies have typically been warned about major vulnerabilities.

Some industry experts have stated that the proximity of the fixes and the data dump is too close to be coincidental, and have begun to speculate upon how Microsoft knew about the exploits one month before the leak. Some say the NSA may have tipped off Microsoft to the leak; others suggest Microsoft secretly paid Shadow Brokers for the vulnerabilities, reports Ars Technica.

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