On Nov. 30 and Dec. 1, 2015, some of the Internet’s Domain Name System (DNS) root name servers received large amounts of anomalous traffic. Last week the root server operators published a report on the incident. In the interest of further transparency, I’d like to take this opportunity to share Verisign’s perspective, including how we identify, handle and react, as necessary, to events such as this.
At Verisign we take our Internet stewardship mission very seriously, so when details emerged over the past week concerning the XcodeGhost infection, researchers at Verisign iDefense wanted to help advance community research efforts related to the XcodeGhost issue, and leveraging our unique capabilities, offer a level of public service to help readers determine their current and historical level of exposure to the infection.
First identified in recent days on the Chinese microblog site Sina Weibo, XcodeGhost is an infection of Xcode, the framework developers use to create apps for Apple’s iOS and OS X operating systems. Most developers download secure Xcode from Apple. However, some acquire unofficial versions from sites with faster download speeds.
Apps created with XcodeGhost contain instructions, unknown to both the app developers and the end users, that collect potentially sensitive information from the user’s device and send it to command-and-control (C2) servers managed by the XcodeGhost operator. This way, the XcodeGhost operators circumvented the security of Apple’s official Xcode distribution, and the security of Apple’s App Store.
The infection had widespread impact. As of September 25th, Palo Alto Networks and Fox-IT had identified more than 87 infected apps by name, and FireEye claimed to have identified more than 4,000 infected apps. This activity impacts millions of users both in China and elsewhere in the world. To understand key aspects of the infection, iDefense researchers leveraged authoritative DNS traffic patterns to the C2 domains.
With the ease of access to the internet and prevalence of social media today, unsuspecting computer users are making it easier than ever for malicious actors to target them with malcode. This trend has helped provide the perfect environment for Distributed Denial of Service (DDoS) attacks to grow in size, complexity and range of targets. Today’s attacks are not limited to web infrastructure; attackers are increasingly targeting the Domain Name System (DNS) infrastructure as well. This trend has been particularly noticeable in the financial industry, which has been hit hard over the last year.