Dark Reading is part of the Informa Tech Division of Informa PLC

This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them.Informa PLC's registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 8860726.

Attacks/Breaches

4/10/2012
01:34 PM
Connect Directly
Google+
Twitter
RSS
E-Mail
50%
50%

Massive Mac Trojan Attack Still Under Way

New, free Flashback Trojan detection and removal tool available from Kaspersky Lab; snapshot of bot counts dropping

[UPDATE 4/11/12: Apple last night announced on its support website that it is developing software that will remove the Flashback Trojan and that it is "working with ISPs worldwide to disable this command and control network" for the Flashback botnet.]

What may have been the largest known botnet made up of Apple Macintosh computers appears to be gradually waning in activity, and there's now a free detection and removal tool available online for Mac users to check whether they are infected by the so-called Flashback Trojan.

Kaspersky Lab -- which is offering the free tool -- counted up to 670,000 infected OS X machines in the botnet last week; today has seen just 227,493 so far, up from 208,301 yesterday. Over the weekend, Kaspersky saw a major dip in the number of active infected Macs, from a head count on Friday, April 6, of 650,748, to 248,723 on Saturday, and then 237,103 on Sunday.

Alex Gostev, Kaspersky's chief security expert, says the number of bots counted here are active ones, and that the numbers don't reflect the total number of infected machines. Kaspersky's online detection and removal tool is available here.

"The drop in unique bots is most likely caused by efforts on the DNS [Domain Name System) levels. For example, a certain DNS could ban access to Flashback domains, which stops users from connecting to the malicious C&C servers, as well as our sinkhole," Gostev says.

But the floodgates have been opened for targeting Macs, and security experts say this is only the beginning. "With more than 100 million Mac OS X users globally, we expect future threats to arise -- we’ve already seen them increase, with attacks such as DNSChanger, Fake AV/Scareware, and the most recent version of the Flashback Trojan/Flashfake botnet. The spike in attacks started in September 2011 and has reached its highest peak in March 2012," Gostev says. "Cybercriminals recognize Mac OS X is gaining market share, especially in developed countries, and we expect them to continue to create ways to infect users."

[Mac users might not have a lot of exploits to worry about, but their lack of security worries makes them an APT attacker's dream come true. See Anatomy Of A Mac APT Attack. ]

The Mac attack scare started last week when researchers at Russian antivirus firm Dr. Web announced they had spotted a botnet of 500,000 to 600,000 Macs, a finding that later was confirmed by Kaspersky Lab and Unveillance. The news was a painful wakeup call for the Mac user community, which long has been spared the bull's eye of botmasters who traditionally have gone after Windows machines. It was no surprise to security experts, however, who for some time have warned that with the Mac's growing popularity -- especially in enterprise circles -- it was only a matter of time before attackers would zero in on the Mac as well.

Kaspersky malware expert Igor Soumenkov late last week said his team found more than 600,000 unique bots reaching out to its server in less than 24 hours, and more than 50 percent were based in the U.S. Kaspersky sinkholed bots that were communicating with one of the Flashback/Flashfake Trojan domain names last week.

Unveillance, meanwhile, has spotted new infections this week: Last night, it counted more than 800,000 unique public IPs sporting Flashback infections, and that number is rising today as well, according to Karim Hijazi, CEO and president of botnet-tracker Unveillance.

"I am sure we will see it drop, but it will take time for the tool to make the rounds through the infected populous," Hijazi says.

Noticeably silent in all of this is Apple, which rarely speaks to the press or comments publicly on security updates or issues. Apple had not responded to a press inquiry as of this posting.

Meanwhile, Forbes reports that Apple attempted to take down Dr. Web's sinkhole server for the Flashback botnet, possibly mistaking it for a malicious command and control domain. Boris Sharov, chief executive of Dr. Web, told Forbes that a Russian registrar informed him that Apple had asked it to shut down the sinkhole domain. "They told the registrar this [domain] is involved in a malicious scheme, which would be true if we weren't the ones controlling it and not doing any harm to users," Sharov told Forbes. "This seems to mean that Apple is not considering our work as a help. It's just annoying them."

But Sharov said in the interview that he thinks Apple mistook his sinkhole for a malicious C&C server.

Kaspersky's Gostev says while his company has worked independently of Apple on this case, from what Kaspersky has seen, "Apple is taking appropriate action by working with the larger Internet security community to shut down the Flashfake C2 domains."

The Flashback variant is being used for click fraud, and exploits a very recently patched Apple OS X Java flaw in order to hijack search engine results. Users are redirected to a malicious website from an infected one after downloading a phony update for Adobe Flash Player. Apple patched the flaws that the Trojan is exploiting last week, and attackers have exploiting similar flaws since February.

Kaspersky provided details of its bot-count in a blog post last night.

Have a comment on this story? Please click "Add Your Comment" below. If you'd like to contact Dark Reading's editors directly, send us a message.

Kelly Jackson Higgins is the Executive Editor of Dark Reading. She is an award-winning veteran technology and business journalist with more than two decades of experience in reporting and editing for various publications, including Network Computing, Secure Enterprise ... View Full Bio

Comment  | 
Print  | 
More Insights
Comments
Newest First  |  Oldest First  |  Threaded View
MSTEWART2600
50%
50%
MSTEWART2600,
User Rank: Apprentice
4/20/2012 | 9:41:45 PM
re: Massive Mac Trojan Attack Still Under Way
On my Macbook, the user agreement doesn't completely fit on the screen, and I can't affirm my agreement, which means I can't download the patch.- Anyone else having this problem or, better yet, figure out a way around it?
44% of Security Threats Start in the Cloud
Kelly Sheridan, Staff Editor, Dark Reading,  2/19/2020
Zero-Factor Authentication: Owning Our Data
Nick Selby, Chief Security Officer at Paxos Trust Company,  2/19/2020
Register for Dark Reading Newsletters
White Papers
Video
Cartoon
Current Issue
6 Emerging Cyber Threats That Enterprises Face in 2020
This Tech Digest gives an in-depth look at six emerging cyber threats that enterprises could face in 2020. Download your copy today!
Flash Poll
How Enterprises Are Developing and Maintaining Secure Applications
How Enterprises Are Developing and Maintaining Secure Applications
The concept of application security is well known, but application security testing and remediation processes remain unbalanced. Most organizations are confident in their approach to AppSec, although others seem to have no approach at all. Read this report to find out more.
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2020-8818
PUBLISHED: 2020-02-25
An issue was discovered in the CardGate Payments plugin through 2.0.30 for Magento 2. Lack of origin authentication in the IPN callback processing function in Controller/Payment/Callback.php allows an attacker to remotely replace critical plugin settings (merchant ID, secret key, etc.) and therefore...
CVE-2020-8819
PUBLISHED: 2020-02-25
An issue was discovered in the CardGate Payments plugin through 3.1.15 for WooCommerce. Lack of origin authentication in the IPN callback processing function in cardgate/cardgate.php allows an attacker to remotely replace critical plugin settings (merchant ID, secret key, etc.) and therefore bypass ...
CVE-2020-9385
PUBLISHED: 2020-02-25
A NULL Pointer Dereference exists in libzint in Zint 2.7.1 because multiple + characters are mishandled in add_on in upcean.c, when called from eanx in upcean.c during EAN barcode generation.
CVE-2020-9382
PUBLISHED: 2020-02-24
An issue was discovered in the Widgets extension through 1.4.0 for MediaWiki. Improper title sanitization allowed for the execution of any wiki page as a widget (as defined by this extension) via MediaWiki's } parser function.
CVE-2020-1938
PUBLISHED: 2020-02-24
When using the Apache JServ Protocol (AJP), care must be taken when trusting incoming connections to Apache Tomcat. Tomcat treats AJP connections as having higher trust than, for example, a similar HTTP connection. If such connections are available to an attacker, they can be exploited in ways that ...