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Be More Effective, Be More Efficient: The Mantra for Many Adversaries in 2014

Adversaries are committed to continually refining or developing new techniques to conceal malicious activity, decrease their reliance on other techniques that may be more detectable, and become increasingly more efficient and effective in their attacks. Below are just three examples—explored in detail in the newly released Cisco 2015 Annual Security Report—of how malicious actors met these goals in 2014. These trends were observed by Cisco Talos Security Intelligence and Research Group throughout last year, and analyzed by the team using a global set of telemetry data:

  • Use of malvertising to help deliver exploit kits more efficiently—Talos noted three exploit kits we observed “in the wild” more than others in 2014: Angler, Goon, and Sweet Orange. More than likely, their popularity is due to their technical sophistication in terms of their ability to evade detection and remain effective. The Sweet Orange kit, for example, is very dynamic. Its components are always changing. Adversaries who use Sweet Orange often rely on malvertising to redirect users (often twice) to websites that host the exploit kit, including legitimate websites.
  • Increase in Silverlight exploitation—As we reported in both the Cisco 2014 Midyear Security Report and the Cisco 2015 Annual Security Report, the number of exploit kits able to exploit Microsoft Silverlight is growing. While still very low in number compared to more established vectors like Flash, PDF, and Java, Silverlight attacks are on the rise. This is another example of adversaries exploring new avenues for compromise in order to remain efficient and effective in launching their attacks. The Angler and Goon exploit kits both include Silverlight vulnerabilities. Fiesta is another known exploit kit that delivers malware through Silverlight, which our team reported on last year.

snowshoe

  • The rise of “snowshoe spam”—Phishing remains an essential tool for adversaries to deliver malware and steal users’ credentials. These actors understand that it is more efficient to exploit users at the browser and email level, rather than taking the time and effort to attempt to compromise servers. To ensure their spam campaigns are effective, Talos observed spammers turning to a new tactic last year: snowshoe spam. Unsolicited bulk email is sent using a large number of IP addresses and at a low message volume per IP address; this prevents some spam systems from detecting the spam, helping to ensure it reaches its intended audience. There is also evidence that adversaries are relying on compromised users’ machines as a way to support their snowshoe spam campaigns more efficiently. Snowshoe spam contributed to the overall increase of spam volume by 250 percent in 2014.

These are only a few of the threat intelligence findings presented in the Cisco 2015 Annual Security Report. We encourage you to read the whole report, but also, to stay apprised of security trends throughout the year by following our reports on the Cisco Security blog. Talos is committed to ongoing coverage of security threats and trends. In fact, in the Cisco 2015 Annual Security Report, you’ll find links to several posts that our researchers published throughout 2014, and were used to help shape and inform our threat intelligence coverage in the report.

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Engaging All Layers of Defense: Incident Response in Action

The Cisco 2015 Annual Security Report highlights many creative techniques that attackers are exploiting to conceal malicious activity, often taking advantage of gaps in security programs. They are continually refining and developing new techniques to gain a foothold in environments and, increasingly, they are relying on users and IT teams as enablers of attacks to persistently infect and hide in plain sight on machines.

Given this complex and dynamic threat landscape, organizations need a mature and adaptable incident response process.

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Dridex Is Back, then it’s gone again

This post was authored by Armin Pelkmann and Earl Carter.

Talos Security Intelligence and Research Group noticed a reappearance of several Dridex email campaigns, starting last week and continuing into this week as well. Dridex is in a nutshell, malware designed to steal your financial account information. The attack attempts to get the user to install the malicious software on their system through an until lately, rarely exploited attack vector: Microsoft Office Macros. Recently, we noticed a resurgence of macro abuse. If macros are not enabled, social engineering techniques are utilized to try to get the user to enable them. Once the malware is installed on the system, it is designed to steal your online banking credentials when you access your banking site from an infected system.

Talos analyzed three separate campaigns in the last days, all distinguishable from their subject lines. Read More »

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Help! My IP Address Has Been Hijacked!

SpamCop is a free, community-based spam email reporting service provided by Cisco. SpamCop analyzes reported spam, and extracts details about the sending IP, the URLs contained in the spam, and the networks over which the spam message has transited. This information is used to create the SpamCop Block List (SCBL). The SCBL a list of IP addresses believed to be sending Unsolicited Bulk Email.

As part of its service, each week SpamCop sends millions of email messages to notify network administrators about malicious activity that is observed occurring on their networks. SpamCop receives all types of replies in response to our notification emails. Many times recipients of SpamCop’s notifications will reply to SpamCop and claim, “we did not send the spam”. The SpamCop Deputies responsible for following up on these replies have heard every excuse under the sun. For them, “we did not send the spam” is the spam block list equivalent of “the dog ate my homework.”

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Snowshoe Spam Attack Comes and Goes in a Flurry

This post is co-authored by Jaeson Schultz and Craig Williams.

Every so often, we observe certain spam campaigns that catch our interest. On August 15, we observed a particular spam campaign that caught our attention because it was using “snowshoe” spam techniques combined with PDF exploitation. While neither of these techniques are new, we have seen a growing trend involving snowshoe spam and we wanted to explain why the bad guys seem to be moving in that direction with a real world example. As you can see from the chart below, we’ve seen the amount of snowshoe spam double since November of 2013.

Snowshoe Spam Chart

Snowshoe spam can be a challenge for some anti-spam detection techniques because it typically uses multiple IP addresses with very low spam volume per IP address. Depending on how an anti-spam technology works, this can cause severe problems with detection. Typically technologies that use multiple defensive layers of protection, like Cisco’s ESA, are much more successful at combating snowshoe spam. We’ve previously discussed these tactics in a previous blog post.

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