Microsoft warns Azure customers of flaw that could have permitted hackers access to data
SAN FRANCISCO - Microsoft (MSFT.O) warned some of its Azure
cloud computing customers that a flaw discovered by security researchers could
have allowed hackers access to their data.
In a blog post from its security response team, Microsoft said
it had fixed the flaw reported by Palo Alto Networks and it had no evidence
malicious hackers had abused the technique.
It said it had notified some customers they should change
their login credentials as a precaution.
The blog post followed questions from Reuters about the
technique described by Palo Alto. Microsoft did not answer any of the
questions, including whether it was confident no data had been accessed.
In an earlier interview, Palo Alto researcher Ariel Zelivansky told Reuters his team had been able to break out of Azure's widely used system for so-called containers that store programs for users.
The Azure containers used code that had not been updated to
patch a known vulnerability, he said.
As a result the Palo Alto team was able to eventually get
full control of a cluster that included containers from other users.
"This is the first attack on a cloud provider to use
container escape to control other accounts," said longtime container
security expert Ian Coldwater, who reviewed Palo Alto's work at Reuters'
request.
Palo Alto reported the issue to Microsoft in July.
Zelivansky said the effort had taken his team several months and he agreed that
malicious hackers probably had not used a similar method in real attacks.
Still, the report is the second major flaw revealed in
Microsoft's core Azure system in as many weeks. In late August, security experts
at Wiz described a database flaw that also would have allowed one customer to
alter another's data.
In both cases, Microsoft's acknowledgment focused on those
customers who might have been somehow affected by the researchers themselves,
rather than everyone put at risk by its own code.
"Out of an abundance of caution, notifications were
sent to customers potentially affected by the researcher activities,"
Microsoft wrote on Wednesday.
Coldwater said the problem reflected a failure to apply
patches in a timely fashion, something Microsoft has often blamed its customers
for.
"Keeping code updated is really important,"
Coldwater said. "A lot of the things that made this attack possible would
no longer be possible with modern software."
Coldwater said that some security software used by cloud
customers would have detected malicious attacks like the one envisioned by the
security company, and that logs would also show signs of any such activity.
The research underscored the shared responsibility between
cloud providers and customers for security.
Zelivansky said cloud architectures are generally safe,
while Microsoft and other cloud providers can make fixes themselves, rather
than rely on customers to apply updates.
But he noted that cloud attacks by well-funded adversaries,
including national governments, are "a valid concern."
Comments
Post a Comment