Vulnerabilities / Threats
3/25/2009
04:33 PM
Connect Directly
Google+
LinkedIn
Twitter
RSS
E-Mail
50%
50%

DSL Modems Becoming Botnet Zombies

Cybercriminals are using the PSYB0T botnet to take advantage of vulnerabilities in the NetComm NB5 modem-router.

Botnets -- groups of computers that have been compromised, hijacked, and coordinated for malicious purposes -- remain a significant source of online security problems. Now some of the zombie machines that constitute botnets have taken on a new form.

For the past few months, security researchers have watched a botnet being built out of embedded devices, specifically DSL modem-routers.

In a paper published in January, security researcher Terry Baume observed that vulnerabilities in the NetComm NB5, an ADSL/ADSL2+ modem-router, have become widely known and that cybercriminals have been taking advantage of these flaws to compromise the devices and, possibly, other modem-routers. He calls the botnet PSYB0T.

"This is the first botnet I've heard of that infects embedded devices," his paper says, noting that a compromised router can be used to alter DNS routing and redirect network traffic to phishing sites.

Baume says that end users aren't likely to be aware that their modem-routers have been compromised and that they could easily become confused if notified by their Internet service provider about possible malware on their computers, which might appear clean to antivirus software.

He also observes that most users leave their DSL modems on all the time. Compromised devices thus would remain active all the time, unlike compromised computers, which tend to get turned off periodically.

DroneBL, a site that monitors IP addresses for abuse, was hit by a distributed denial-of-service (DDoS) attack from a PSYB0T botnet for several weeks.

A blog post on the site explains that in order to be vulnerable, the device in question must be a Linux mipsel device; must have telnet, SSH, or a Web-based interface available over a WAN; and must have weak user name/password combinations or must have firmware that relies on daemons that are exploitable.

"The malware can spread itself through telnet admin interfaces of the DSL modems," a post on the Team Furry blog explains. "It also has the capability to scan for PHPMyAdmin installations and Windows SMB shares."

Devices not running MIPS, such the x86-based computers run by most consumers, are not themselves at risk, but could be affected if connected to vulnerable DSL modems.

Owners of potentially vulnerable DSL modem-routers are advised to make sure the devices have updated firmware and to verify that they're using a user name and password for the device that can't be easily guessed by a dictionary attack.


Find out how to balance technology, business intelligence, and process to reduce exposure to vulnerabilities (registration required).

Comment  | 
Print  | 
More Insights
Register for Dark Reading Newsletters
White Papers
Cartoon
Current Issue
Dark Reading Tech Digest, Dec. 19, 2014
Software-defined networking can be a net plus for security. The key: Work with the network team to implement gradually, test as you go, and take the opportunity to overhaul your security strategy.
Flash Poll
Video
Slideshows
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2004-2771
Published: 2014-12-24
The expand function in fio.c in Heirloom mailx 12.5 and earlier and BSD mailx 8.1.2 and earlier allows remote attackers to execute arbitrary commands via shell metacharacters in an email address.

CVE-2014-3569
Published: 2014-12-24
The ssl23_get_client_hello function in s23_srvr.c in OpenSSL 1.0.1j does not properly handle attempts to use unsupported protocols, which allows remote attackers to cause a denial of service (NULL pointer dereference and daemon crash) via an unexpected handshake, as demonstrated by an SSLv3 handshak...

CVE-2014-4322
Published: 2014-12-24
drivers/misc/qseecom.c in the QSEECOM driver for the Linux kernel 3.x, as used in Qualcomm Innovation Center (QuIC) Android contributions for MSM devices and other products, does not validate certain offset, length, and base values within an ioctl call, which allows attackers to gain privileges or c...

CVE-2014-6132
Published: 2014-12-24
Cross-site scripting (XSS) vulnerability in the Web UI in IBM WebSphere Service Registry and Repository (WSRR) 6.3 through 6.3.0.5, 7.0.x through 7.0.0.5, 7.5.x through 7.5.0.4, 8.0.x before 8.0.0.3, and 8.5.x before 8.5.0.1 allows remote authenticated users to inject arbitrary web script or HTML vi...

CVE-2014-6153
Published: 2014-12-24
The Web UI in IBM WebSphere Service Registry and Repository (WSRR) 6.3.x through 6.3.0.5, 7.0.x through 7.0.0.5, 7.5.x through 7.5.0.4, 8.0.x before 8.0.0.3, and 8.5.x before 8.5.0.1 does not set the secure flag for a cookie in an https session, which makes it easier for remote attackers to capture ...

Best of the Web
Dark Reading Radio
Archived Dark Reading Radio
Join us Wednesday, Dec. 17 at 1 p.m. Eastern Time to hear what employers are really looking for in a chief information security officer -- it may not be what you think.