Attacks/Breaches
2/1/2010
02:50 PM
Connect Directly
Google+
Twitter
RSS
E-Mail
50%
50%

Botnet Floods Major Websites With Fake SSL Connections

DDoS-like traffic surge against CIA, Chase, Google Chrome, FBI, and others has researchers puzzled by Pushdo botnet's plans

A spamming botnet known for keeping a low profile has been hammering hundreds of Websites -- including the CIA, Chase, Mozilla Labs, Twitter, SANS, Google Chrome, and the FBI -- during the past week with an unusually conspicuous amount of phony traffic that has researchers rushing to analyze its next move.

The Pushdo botnet, a.k.a. "Cutwail" and "Pandex," has been flooding those sites with bogus SSL connections that stop short of requesting anything from the Website. The infected bots begin to initiate an SSL connection with some "junk" traffic and then disconnect, according to The Shadowserver Foundation. Shadowserver and other researchers have been monitoring the activity, which increased traffic by several million hits across several hundred thousand IP addresses, according to Shadowserver.

The botnet hit the ZeusTracker Website, for example, with hundreds of thousands of different IP addresses within a 24-hour period. "This is a lot of bots generating a lot of traffic," blogged Steven Adair, a researcher with Shadowserver. Recent code changes to Pushdo resulted in its bots generating the "junk" SSL connections to the 315 Websites, he said.

So what is Pushdo up to? Joe Stewart, director of malware research for Secureworks, says the botnet is making fake SSL connection attempts: Malformed packets cause the server to return an SSL negotiation error. "By adding the initial header of an SSL conversation, they may be attempting to avoid closer scrutiny by less vigilant inspection devices," Stewart says. "And by sending a flurry of these connections to a number of legit 'decoy' sites, it helps the Pushdo C&C [command and control] traffic blend in and remain undetected in some cases," he says.

It's unclear thus far whether this is a test-run for phony SSL connections gone amuck that ended up exposing this Pushdo traffic, or something else. Stewart says it's possible there could be more to the latest activity, such as the botnet's rotating its target lists. "It's hard to say," he says.

Blending in has traditionally been Pushdo's trademark: Although it's one of the top five spamming botnets, it's also one of the more under-the-radar botnets around. But this latest activity has researchers wondering how this massive surge of traffic, which resembles a distributed denial-of-service (DDoS) attack, would ultimately help its traffic blend in and become less detectable.

Shadowserver says the traffic is technically an attack, even though it doesn't appear to be trying to knock the sites offline like a DDoS does. "We find it hard to believe this much activity would be used to make the bots blend in with normal traffic, but at the same time it doesn't quite look like a DDoS either," Adair says.

Secureworks' Stewart says he has witnessed botnets sending traffic via SSL or port 443, but this phony SSL connection attempt is a first. "The Pushdo C&C protocol now also uses similar packets to encapsulate its encrypted/compressed phone-home requests," he says. "Port 443 is commonly being used to proxy all kinds of non-SSL traffic by legit applications and bots alike, so it stands to reason that a heuristic one might look for suspicious or firewall-policy-violating traffic connections over port 443 that aren't using SSL. "

The surge in traffic from Pushdo could cause problems for Websites with limited bandwidth and that typically get only a few hundred to a few thousand hits daily, Shadowserver says.

Have a comment on this story? Please click "Discuss" 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
Register for Dark Reading Newsletters
White Papers
Flash Poll
Current Issue
Cartoon
Video
Slideshows
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2014-0103
Published: 2014-07-29
WebAccess in Zarafa before 7.1.10 and WebApp before 1.6 stores credentials in cleartext, which allows local Apache users to obtain sensitive information by reading the PHP session files.

CVE-2014-0475
Published: 2014-07-29
Multiple directory traversal vulnerabilities in GNU C Library (aka glibc or libc6) before 2.20 allow context-dependent attackers to bypass ForceCommand restrictions and possibly have other unspecified impact via a .. (dot dot) in a (1) LC_*, (2) LANG, or other locale environment variable.

CVE-2014-0889
Published: 2014-07-29
Multiple cross-site scripting (XSS) vulnerabilities in IBM Atlas Suite (aka Atlas Policy Suite), as used in Atlas eDiscovery Process Management through 6.0.3, Disposal and Governance Management for IT through 6.0.3, and Global Retention Policy and Schedule Management through 6.0.3, allow remote atta...

CVE-2014-2226
Published: 2014-07-29
Ubiquiti UniFi Controller before 3.2.1 logs the administrative password hash in syslog messages, which allows man-in-the-middle attackers to obtains sensitive information via unspecified vectors.

CVE-2014-3020
Published: 2014-07-29
install.sh in the Embedded WebSphere Application Server (eWAS) 7.0 before FP33 in IBM Tivoli Integrated Portal (TIP) 2.1 and 2.2 sets world-writable permissions for the installRoot directory tree, which allows local users to gain privileges via a Trojan horse program.

Best of the Web
Dark Reading Radio