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Shellshock Exploits in the Wild

This post was authored by Joel Esler & Martin Lee.

The recently discovered Bash vulnerability (CVE-2014-6271) potentially allows attackers to execute code on vulnerable systems. We have already blogged about the issue and provided more technical detail in a further blog. The rapid release of IPS signatures for our platforms allowed us to follow very quickly, the attempts at exploitation of the vulnerability in the wild.

For further details of our response to the issue, please see the Event Response Page.
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Another Major Vulnerability Bashes Systems

Vulnerabilities that permit remote network attacks against ubiquitous software components are the nightmares of security professionals. On 24 September the presence of a new vulnerability, CVE-2014-6271 in Bash shell allowing remote code execution was disclosed.
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Threat Spotlight: “Kyle and Stan” Malvertising Network 9 Times Larger Than Expected

This post was authored by Armin Pelkmann.

On September 8th, Cisco’s Talos Security Intelligence & Research Group unveiled the existence of the “Kyle and Stan” Malvertisement Network. The network was responsible for placing malicious advertisements on big websites like,,, and 70 other domains. As it turns out, this was just the tip of the iceberg. Ongoing research now reveals the real size of the attackers’ network is 9 times larger than reported in our first blog. For more details, read the Kyle and Stan Blog.

The infographic below illustrates how much more of the malvertisement network was uncovered in comparison to our first assessment. We have now isolated 6491 domains sharing the same infrastructure. This is over 9 times the previously mentioned 703 domains.  We have observed and analyzed 31151 connections made to these domains. This equals over 3 times the amount of connections previously observed. The increase in connections is most likely not proportional to the domains due to the fact that a long time that has passed since the initial attacks.


The discovery difference from the previous blog to this one in raw numbers. With more than 3-times the now observed connections and over 9-times the revealed malicious domains, this malvertising network is of unusually massive proportions.

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Threat Spotlight: “Kyle and Stan” Malvertising Network Threatens Windows and Mac Users With Mutating Malware

This post was authored by Shaun Hurley, David McDaniel and Armin Pelkmann.

Update 2014-09-22: Updates on this threat can be found here

img_MetricsHave you visited,,,, or any of the 74 domains listed below lately? If the answer is yes, then you may have been a victim to the “Kyle and Stan” Malvertising Network that distributes sophisticated, mutating malware for Windows and even Macs.

Table of contents

Attack in a Nutshell
Technical Breakdown
Reversing of the Mac Malware
Reversing of the Windows Malware
Protecting Users Against These Threats

Malvertising is a short form for “malicious advertising.” The idea is very simple: use online advertising to spread malware. Read More »

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The increasing prevalence and complexity of malware

In recent months, many organizations are becoming more interested in the information security landscape and how these threats can affect their business today.

In the recent Cisco 2014 Midyear Security Report, the results showed that 90% of select customer networks were found issuing DNS queries to domain names known to be associated with malware distribution. Results also showed an increase in Point of Sale (POS) exploits over the past year. These threats are growing and may put at risk many users using websites where personal or financial information is being submitted. These users need to know how this malware works, that malware is becoming more sophisticated, and that it is becoming increasingly difficult to identify that users’ machines have been compromised by malware. Read More »

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