Social-engineering attacks are increasing, and users need to be more vigilant about what they are opening and downloading.
in which users are tricked into clicking on a link or downloading malicious
programs are far more common than attacks that exploit security vulnerabilities
in software, according to Microsoft.
One out of every 14 programs
downloaded by Windows users later were discovered to be malicious, Jeb Haber,
program manager lead of the SmartScreen
group working on Internet Explorer at Microsoft, wrote May 17 on the IE blog.
Internet Explorer blocked between 2 million and 5 million attacks a day for
Internet Explorer 8 and 9 customers who have enabled the SmartScreen filter
protection, Microsoft said.
"User-downloaded malware is
a huge problem and getting bigger," Haber said.
Originally, SmartScreen in
Internet Explorer 7 was a URL-based filter that obtained lists of bad URLs from
a cloud-based URL-reputation service, according to Microsoft. Internet Explorer
8 enhanced SmartScreen to filter out sites that had social-engineering
techniques. Other major browsers, including Google Chrome and Firefox Mozilla,
also display similar warnings for potential rogue Websites.
Modern Web browsers are
generally more secure than they used to be, and software vendors are getting
better about automatically pushing out patches to fix bugs, Haber said, forcing
attackers to switch tactics to use more social-engineering tricks.
are combined with other attack vectors, such as spam or poisoned links on
search results pages. The Koobface worm proliferated on Facebook because users
saw a message from friends about a cool video to watch. When the user tried to
watch the video, they were instructed to download software that would allow the
video to play, but it was actually malware. There were similar scams for videos
purporting to show the operation that killed Osama bin Laden earlier this
month, as well.
It's not just Windows users
falling for social-engineering tricks. Mac users are, as well. With
MacDefender, MacSecurity and MacProtector fake antivirus on the scene, many Mac
users are falling for the scam, according to Mac security company Intego. "We
are contacted by a huge number of customers who are worried about this fake
antivirus, and have dozens of samples, including a number of variants of the
scareware," the company posted on its Mac
ZDNet's Ed Bott posted a
transcript of his interview with an AppleCare
representative that confirmed that Apple's call centers are hearing
from many users whose machines are infected with MacDefender and its variants.
"It started with one call a day two weeks ago; now it's every other call. It's
getting worse. And quick," the AppleCare representative told Bott.
To help protect users from
social-engineering attacks where users are being conned into downloading files,
Microsoft expanded SmartScreen in Internet Explorer 9 with Application
Reputation. Application Reputation looks at what is being downloaded and
informs users if they are unknown or potentially untrustworthy. "When it comes
to program downloads, other browsers today either warn on every file or don't
warn at all," Haber said.
Application Reputation alone
will prevent more than 20 million additional infections per month, and that's
not counting the URLs blocked by the SmartScreen filters, according to Haber.
Users sometimes see warnings for legitimate software, but that's only because
it is new and "has not yet established a reputation" but that is a "rare
exception," according to Haber. Unsigned programs were the cause of 96 percent
of the warnings that consumers have seen to date and the remaining 4 percent
were the result of Website certificates that had previously been associated
with malware or were newly issued.
Even with Application Reputation
in place, about 5 percent of users ignore the warnings and download malicious
applications anyway, according to Microsoft. On any given day, clicking through
the "unknown" warning page carries a risk between 25 percent and 70 percent of
actually getting a malware infection, according to Haber. A typical user will
only see a couple of these warnings each year, so it's best to take them very