Windows' error- and crash-reporting system sends a wealth of data unencrypted and in the clear, information that eavesdropping hackers or state security agencies can use to refine and pinpoint their attacks, a researcher said today.
Not coincidentally, over the weekend the popular German newsmagazine Der Spiegel reported that the U.S. National Security Agency (NSA) collects Windows crash reports from its global wiretaps to sniff out details of targeted PCs, including the installed software and operating systems, down to the version numbers and whether the programs or OSes have been patched; application and operating system crashes that signal vulnerabilities that could be exploited with malware; and even the devices and peripherals that have been plugged into the computers.
"This information would definitely give an attacker a significant advantage. It would give them a blueprint of the [targeted] network," said Alex Watson, director of threat research at Websense, which on Sunday published preliminary findings of its Windows error-reporting investigation. Watson will present Websense's discovery in more detail at the RSA Conference in San Francisco on Feb. 24.
Sniffing crash reports using low-volume "man-in-the-middle" methods -- the classic is a rogue Wi-Fi hotspot in a public place -- wouldn't deliver enough information to be valuable, said Watson, but a wiretap at the ISP level, the kind the NSA is alleged to have in place around the world, would.
"At the [intelligence] agency level, where they can spend the time to collect information on billions of PCs, this is an incredible tool," said Watson.
And it's not difficult to obtain the information.
Microsoft does not encrypt the initial crash reports, said Watson, which include both those that prompt the user before they're sent as well as others that do not. Instead, they're transmitted to Microsoft's servers "in the clear," or over standard HTTP connections.
If a hacker or intelligence agency can insert themselves into the traffic stream, they can pluck out the crash reports for analysis without worrying about having to crack encryption.
And the reports from what Microsoft calls "Windows Error Reporting" (ERS), but which is also known as "Dr. Watson," contain a wealth of information on the specific PC.
When a device is plugged into a Windows PC's USB port, for example -- say an iPhone to sync it with iTunes -- an automatic report is sent to Microsoft that contains the device identifier and manufacturer, the Windows version, the maker and model of the PC, the version of the system's BIOS and a unique machine identifier.
By comparing the data with publicly-available databases of device and PC IDs, Websense was able to establish that an iPhone 5 had been plugged into a Sony Vaio notebook, and even nail the latter's machine ID.
If hackers are looking for systems running outdated, and thus, vulnerable versions of Windows -- XP SP2, for example -- the in-the-clear reports will show which ones have not been updated.
Windows Error Reporting is installed and activated by default on all PCs running Windows XP, Vista, Windows 7, Windows 8 and Windows 8.1, Watson said, confirming that the Websense techniques of deciphering the reports worked on all those editions.
Watson characterized the chore of turning the cryptic reports into easily-understandable terms as "trivial" for accomplished attackers.