spam

This post was authored by Earl Carter & Jaeson Schultz. Talos is always fascinated by the endless creativity of those who send spam. Miscreants who automate sending spam using botnets are of particular interest. Talos has been tracking a spam botnet that over the past several months that has bee…

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 deta…

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…

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 infor…

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 Blo…

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 expl…

Overview Phishing attacks use social engineering in an attempt to lure victims to fake websites. The websites could allow the attacker to retrieve sensitive or private information such as usernames, passwords, and credit card details. Attacks of this kind have been around since 1995, evolving in sop…

It is not uncommon to see an anti-spam system catch >99% of the spam passing through it. Most of the best anti-spam systems catch >99.9% of spam. In this environment, spammers try just about anything to evade spam filters. Some spammers believe that blasting at high volume is the key to succes…

April kicked off with a 1:292 rate of malware encounters and closed with a rate of 1:315. Highest peak day was April 20 when the rate reached 1:177. Lowest was April 4 at 1:338. The median rate of web malware encounters in April 2014 was 1:292, representing a slight improvement over the median of 1:…