Risk
4/11/2012
05:07 PM
Connect Directly
Google+
Twitter
RSS
E-Mail
50%
50%
Repost This

Linux Users Beware: Patch New Samba Flaw 'Immediately'

Samba bug could spur targeted attacks or a worm -- but not all affected systems will get patched

A dangerous vulnerability in a pervasive tool for running Linux systems in a Windows environment leaves the door open for an attacker to access these systems without requiring any authentication.

The open-source Samba group this week released an update to the Samba program to fix a bug that could allow an attacker to remotely acquire root access to the targeted server. The bug in Samba versions 3.6.3 and previous versions is a buffer overflow flaw in Samba's remote procedure call code. "As this does not require an authenticated connection it is the most serious vulnerability possible in a program, and users and vendors are encouraged to patch their Samba installations immediately," according to a newly issued advisory from Samba on the new CVE-2012-1182 vulnerability, which includes links to patches for the software.

Nicholas Percoco, senior vice president and head of Trustwave SpiderLabs, says the flaw affects anyone who has embedded Linux-based appliances that use Samba for file sharing, such as NASes, print servers, and printers. While these devices tend to run in an intranet rather than over the big Internet, the main risk would be from a sophisticated targeted attack or a malicious insider, he says.

"This is a very critical patch you should be applying ... if an attacker gets root access, it's game over from a security perspective," Percoco says. "You should not be running Samba [systems] on the Internet. That being said, it doesn't mean people aren't."

A proof-of-concept is circulating, and Percoco says the vulnerability is prime for abuse as a network worm as well as for a targeted attack. "It can also be the perfect storm for a Unix-based worm. This is something like the Nimda For Linux/Unix," he says.

But most at risk here is the compromise of Linux-embedded systems that use Samba, and many of these device vendors are notorious for not regularly patching these systems. "Some have firmware that you can have updated. So contact the vendor to see if they have updated firmware for this," Percoco says. "If not, you have to weigh the risk. If you're risk-averse, you may have to unplug or replace these devices."

Many devices won't ever be fixed, Percoco and other security experts say.

[While operating systems and PC applications have evolved fast patch mechanisms, the proliferation of slow-to-patch embedded devices leaves companies vulnerable. See Firms Slow To Secure Flaws In Embedded Devices.]

"Samba is not commonly exposed to the Internet, fortunately. However, most NAS devices, home storage systems, Linux PCs, and Mac OS X PCs that share files over SMB are based on Samba," says HD Moore, chief security officer for Rapid 7 and creator of Metasploit. "For example, I have a couple of home storage arrays that the vendor considers plug and play. In both cases, the SMB server is Samba-based, and not likely to see a patch anytime soon."

Moore says corporate, internal systems would be at risk of attack by malicious internal employees and intruders with access to the corporate network. But users don't always know that their embedded devices use Samba since most of these devices don't exactly broadcast that element, according to Moore.

"The real risk is long-term exploitability of NAS devices, smart printers, and other systems that use the Samba code and don't maintain security patches for the SMB service or systems that you never, ever want to take offline," Moore says.

That would include things such as a NAS: "Taking your NAS offline to patch a core service is something that typically involves a maintenance window and a lot of pain, depending on how many systems are using it," he says.

Meanwhile, Trustwave SpiderLabs posted a blog today on the Samba security update.

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 Senior Editor at DarkReading.com. 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 Magazine, ... View Full Bio

Comment  | 
Print  | 
More Insights
Comments
Newest First  |  Oldest First  |  Threaded View
helix2301
50%
50%
helix2301,
User Rank: Apprentice
4/17/2012 | 8:09:20 PM
re: Linux Users Beware: Patch New Samba Flaw 'Immediately'
I agree everyone know that the Mac is just bsd under neath all that cool look and feel.
lipanitech
50%
50%
lipanitech,
User Rank: Apprentice
4/16/2012 | 12:40:31 PM
re: Linux Users Beware: Patch New Samba Flaw 'Immediately'
I am curious to see how this affects the Apple OSx
Register for Dark Reading Newsletters
White Papers
Cartoon
Current Issue
Video
Slideshows
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2012-3946
Published: 2014-04-24
Cisco IOS before 15.3(2)S allows remote attackers to bypass interface ACL restrictions in opportunistic circumstances by sending IPv6 packets in an unspecified scenario in which expected packet drops do not occur for "a small percentage" of the packets, aka Bug ID CSCty73682.

CVE-2012-5723
Published: 2014-04-24
Cisco ASR 1000 devices with software before 3.8S, when BDI routing is enabled, allow remote attackers to cause a denial of service (device reload) via crafted (1) broadcast or (2) multicast ICMP packets with fragmentation, aka Bug ID CSCub55948.

CVE-2013-6738
Published: 2014-04-24
Cross-site scripting (XSS) vulnerability in IBM SmartCloud Analytics Log Analysis 1.1 and 1.2 before 1.2.0.0-CSI-SCALA-IF0003 allows remote attackers to inject arbitrary web script or HTML via an invalid query parameter in a response from an OAuth authorization endpoint.

CVE-2014-0188
Published: 2014-04-24
The openshift-origin-broker in Red Hat OpenShift Enterprise 2.0.5, 1.2.7, and earlier does not properly handle authentication requests from the remote-user auth plugin, which allows remote attackers to bypass authentication and impersonate arbitrary users via the X-Remote-User header in a request to...

CVE-2014-2391
Published: 2014-04-24
The password recovery service in Open-Xchange AppSuite before 7.2.2-rev20, 7.4.1 before 7.4.1-rev11, and 7.4.2 before 7.4.2-rev13 makes an improper decision about the sensitivity of a string representing a previously used but currently invalid password, which allows remote attackers to obtain potent...

Best of the Web