A memory error is a condition that occurs any time one or more bits being read from memory have changed state from what was previously written. By even the most conservative of estimates Internet devices experience more than 600,000 memory errors per day. Cosmic radiation, operating a device outside its recommended environmental conditions, and defects in manufacturing can all cause a “1” in memory to become a “0” or vice-versa. Most of these bit errors are harmless, but occasionally the bit error occurs inside a domain name or URL, and this can affect where Internet traffic is directed. The term “bitsquatting”, which refers to the practice of registering a domain name one binary digit different than another, is a term coined after a similar term, “cybersquatting” --the practice of registering an unofficial domain which could be confused for a legitimate one.
For example, the fully qualified domain name “www.cisco.com” could by changing only a single binary digit become the bitsquat domain name “wwwncisco.com”. In this example, the dot separating the second and third level domain names has experienced a bit error, and changed to become the letter “n”.
Binary representation of a dot versus the character “n”
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Tags: Bitsquatting, dns, RPZ, TRAC
Network Solutions is a domain name registrar that manages over 6.6 million domains. As of July 16, 2013, the Network Solutions website is under a Distributed Denial of Service (DDoS) attack. Recently, Network Solutions has been a target for attackers; in a previous outage, domain name servers were redirected away from their proper IP addresses. This was reported to be a result of a server misconfiguration while Network Solutions was attempting to mitigate a DDoS attack. It is possible that the DDoS attacks are related.
According to isitdownrightnow.com, the Network Solutions site has been having issues for at least the last 24 hours.
Response time in ms (GMT -8:00)
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Tags: cybersecurity, DDoS, dns, malware, security, TRAC, vulnerability
UPDATE: This blog post is related to the redirection of domain name servers that occurred back in June 2013. This post is NOT related to the ongoing activity occuring July 16, 2013. Cisco TRAC is currently analyzing the ongoing issues with Network Solutions’ hosted domain names and has more information available here.
Multiple organizations with domain names registered under Network Solutions suffered problems with their domain names today, as their DNS nameservers were replaced with nameservers at ztomy.com. The nameservers at ztomy.com were configured to reply to DNS requests for the affected domains with IP addresses in the range 188.8.131.52/24. Cisco observed a large number of requests directed at these confluence-network IP addresses. Nearly 5000 domains may have been affected based on passive DNS data for those IPs.
Traffic hits to 184.108.40.206/24
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Tags: dns, TRAC
This introductory post explains how one of Cisco’s security research groups established a network data collection capability for large amounts of network traffic. This capability was necessary to support research into selected aspects of the Domain Name Service (DNS), but it can be adapted for other purposes.
DNS exploitation is frequently the means by which malicious actors seek to disrupt the normal operation of networks. This can include DNS Cache Poisoning, DNS Amplification Attacks and many others. A quick search at cisco.com/security yields a lot of content published, indicating both the criticality and exposures associated with DNS.
Our research required the ability to collect DNS data and extract DNS attributes for various analytical purposes. For this post, I’ll focus on collection capabilities regarding DNS data. Read More »
Tags: data analytics, data collection, dns, netflow, security
Are you excited about March Madness? Turn on a TV and it will be hard to avoid the games, the news, the commentaries, and the jokes about it. If you eavesdrop in any restaurant, bar, or office conversation, I can assure you that you will hear something about it. Even U.S. President Barack Obama filled out a March Madness bracket. Productivity in many offices drops significantly as employees search and watch videos to see how their bracket picks are progressing. At Cisco, we have an open policy and employees can watch and search the scores of their favorite teams. Watch this video posted by CNN where Kip Compton, Cisco’s Video Collaboration Group CTO, talks about March Madness.
A few things to keep in mind:
- Legitimate business sites may have vulnerabilities that allow a hostile site to deliver malware.
- In most drive-by downloads, the victim is willing to dismissively click pop-ups and warnings as they navigate to the desired content. In this case, users may just click on pop-ups or ads to watch videos about their favorite team.
- Most drive-by downloads can be prevented by keeping software up to date. Read More »
Tags: Cisco Security, cisco sio, crimeware, dns, exploit kit, java vulnerability, malware, march madness, XSS