Hidden Lynx-Professional Hackers for Hire

SECURITY RESPONSE The Hidden Lynx group is a professional team of attackers with advanced capabilities. Follow us on Twitter @threatintel Visit our Blog http://www.symantec.com/connect/symantec-blogs/sr Hidden Lynx – Professional Hackers for Hire Stephen Doherty, Jozsef Gegeny, Branko Spasojevic, Jonell Baltazar Version 1.0 – September 17, 2013 CONTENTS OVERVIEW ..................................................................... 3 Background ................................................................... 5 Who are the Hidden Lynx group? .................................. 5 Who are their targets? .................................................. 7 What is their motivation? .............................................. 7 Corporate Espionage ............................................... 8 Attacks against government contractors ................ 8 What are they capable of? ............................................ 8 Subverting trust protection models ........................ 8 Advanced zero-day access .................................... 13 Supply chain attacks ............................................. 14 Conclusion ................................................................... 16 Appendix ..................................................................... 18 Related attacks ...................................................... 18 Resources .................................................................... 25 Symantec Protection ................................................... 26 The Hidden Lynx group is a professional team of attackers with advanced capabilities. They were responsible for the compromise of security firm Bit9’s digital code-signing certificate which was used to sign malware. The Bit9 breach was part of the much larger VOHO campaign and that campaign was just one of many operations undertaken by the group over the last four years. The group likely offers a “hackers for hire” operation and is tasked with retrieving specific information from a wide range of corporate and government targets. They are a highly efficient team who can undertake multiple campaigns at once, breach some of the world’s best-protected organizations and can change their tactics quickly to achieve their goal. They usually attack using multiple customized Trojans designed for specific purposes. Backdoor.Moudoor is used for larger campaigns and has seen widespread distribution while Trojan.Naid is reserved for special operations against high value targets. The group uses cutting-edge attack techniques which makes this team stand out from other major attack groups. This paper takes an in-depth look at the Hidden Lynx group, their targets and their motivations. It will look into their capabilities and attack strategies through their attack campaigns including the Bit9 incident. OVERVIEW A well-known group with affiliations to “Operation Aurora” managed to break into Bit9’s network using an SQL injection attack. BACKGROUND Page 5 Hidden Lynx – Professional Hackers for Hire Background In February 2013, Bit9 released a statement revealing that in July 2012, their network had been compromised by a malicious third-party. A well-known group named Hidden Lynx with affiliations to “Operation Aurora” managed to break into Bit9’s network using an SQL injection attack. These Trojans made their way into the defense industrial sector. However, the Bit9 compromise was only a small piece of a much larger watering-hole operation known as the VOHO campaign, which impacted hundreds of organizations in the United States. Further, the VOHO campaign itself was just one campaign of many that is attributable to this incredibly prolific group. Each campaign is designed to access information in governmental and commercial organizations that tend to operate in the wealthiest and most technologically advanced countries in the world. Who are the Hidden Lynx group? The Hidden Lynx group has been in operation since at least 2009 and is most likely a professional organization that offers a “hackers for hire” service. They have the capability to attack many organizations with concurrently running campaigns. They operate efficiently and move quickly and methodically. Based on these factors, the Hidden Lynx group would need to be a sizeable organization made up of between 50 and 100 individuals. The members of this group are experts at breaching systems. They engage in a two-pronged strategy of mass exploitation and pay-to-order targeted attacks for intellectual property using two Trojans designed specifically for each purpose: • Team Moudoor distributes Backdoor.Moudoor, a customized version of “Gh0st RAT”, for large-scale campaigns across several industries. The distribution of Moudoor requires a sizeable number of people to both breach targets and retrieve the information from the compromised networks. • Team Naid distributes Trojan.Naid, the Trojan found during the Bit9 incident, which appears to be reserved for more limited attacks against high value targets. This Trojan was leveraged for a special operation during the VOHO campaign and is probably used by a specific team of highly skilled attackers within the group. This Trojan was also found as part of “Operation Aurora” in 2009. Much of the attack infrastructure and tools used during these campaigns originate from network infrastructure in China. The Hidden Lynx group makes regular use of zero-day exploits and has the ability to rework and customize exploits quickly. They are methodical in their approach and they display a skillset far in advance of some other attack groups also operating in that region, such as the Comment Crew (also known as APT1). The Hidden Lynx group is an advanced persistent threat that has been in operation for at least four years and is breaking into some of the best-protected organizations in the world. With a zero-day attack already under their belt in 2013, they continue to operate at the leading edge of targeted attacks. The diverse set of targets from a variety of sectors would indicate that this group is not focused on any one specific task. WHO ARE THEIR TARGETS? Page 7 Hidden Lynx – Professional Hackers for Hire Who are their targets? Since November 2011, hundreds of organizations worldwide have been targeted by the Hidden Lynx group. These organizations have remained relatively consistent during this time period. The group targets organizations operating in both the commercial sector and within all levels of government. The diverse set of targets from a variety of sectors would indicate that this group is not focused on any one specific task. The group manages concurrent campaigns in attacks that are global in nature. The Hidden Lynx group has most recently conducted attacks against specific organizations in South Korea and has a long history of attacking the defense industrial sector of Western countries. The top 10 organizations categorized by the verticals they belong to are shown in Figure 1. The most targeted countries/regions are shown in Figure 2. What is their motivation? This broad range of targeted information would indicate that the attackers are part of a professional organization. They are likely tasked with obtaining very specific information that could be used to gain competitive advantages at both a corporate and nation state level. It is unlikely that this organization engages in processing or using the stolen information for direct financial gain. Their mode of operation would suggest that they may be a private organization of “hackers for hire”, who are highly skilled, experienced professionals whose services are available for those willing to pay. Figure 1. Top 10 organizations targeted by the Hidden Lynx group since November 2011 Figure 2. Countries/regions targeted by the Hidden Lynx group since November 2011 Page 8 Hidden Lynx – Professional Hackers for Hire Corporate Espionage The financial services sector has been identified as the most heavily targeted industry overall. There is a tendency to target specific companies within this sector. Investment banks and asset management agencies account for the majority of organizations targeted within this industry. The absence of certain types of financial institutions, such as those operating as commercial banks, clearly indicates that the attacks are focusing on specific areas. The organizations involved would have expertise in large corporate deals, such as confidential information on upcoming mergers and acquisitions, which could be used to gain a competitive edge. Targeting this sector in such a concentrated fashion could provide invaluable information when negotiating large takeovers or trading shares on the stock exchange. Attacks on the financial sector are not limited to investment banks. Stock trading firms and one of the world’s largest stock exchanges have been subjected to attacks from this group. The Hidden Lynx group has also undertaken indirect attacks through the supply chains. Organizations that supply hardware, secure network communications and services specific to the financial sector have also come under attack. There is almost certainly a financial motivation behind these attacks. Attacks against government contractors In attacks that have targeted all levels of government from local to national level, this group has repeatedly attempted to infiltrate these networks. Attacks against government contractors and, more specifically, the defense industry indicate that the group is in pursuit of confidential information and suggests that the group had been working for nation states. Targeting advanced technologies in specific areas such as aerospace would be useful in order to close technological gaps or gain knowledge of the advanced capabilities of other nation states. Attacks on organizations that operate in the Internet services space can provide a wealth of valuable information. The group had affiliations to “Operation Aurora” (See appendix for more details), a campaign that targeted a number of organizations including software manufacturers and defense contractors. More recently, Microsoft claimed that the target was databases containing emails marked for court order wiretaps. They believe that these attacks were counter-intelligence operations, activities that would provide benefits at a nation state level. What are they capable of? The group’s tools, tactics and procedures are innovative and typically cutting-edge. They use custom tools and techniques that they tailor to meet their objectives and maximize their chance of success. They attack public- facing infrastructure and have been observed installing highly customized Trojans that are purpose-built for stealth. They engineered one of the most successful watering-hole attacks to-date. They also undertake spear- phishing attacks and hack supply chains in order to distribute their custom Trojans. This is an established team with years of experience. They are well resourced and highly skilled. The Hidden Lynx group’s advanced capabilities are clearly demonstrated in three major campaigns. In the VOHO campaign, they showed how they could subvert Bit9’s established trust models. In the FINSHO campaign, they managed to get advanced knowledge of a zero-day exploit and in the SCADEF operation, they undertook supply chain attacks to succeed in their campaign. Subverting trust protection models The team can adapt rapidly to counter-measures that would otherwise hinder the success of a campaign. The attack on Bit9 showed how the group could bypass solid trust protection models to get to their targets. However, this attack was only a small part of the larger VOHO campaign, where the group proved how quickly they can adapt and change their tactics in the face of new and unforeseen obstacles. Page 9 Hidden Lynx – Professional Hackers for Hire The Bit9 incident Bit9 is a security company headquartered in Waltham, Massachusetts. As an alternative to traditional signature-based antivirus solutions, Bit9 offers a trust-based security platform that runs off of a cloud-based reputation service combined with policy-driven application control and whitelisting to protect against cyberthreats. As a result, it is difficult for a malicious third-party to install an untrusted application, such as a remote access Trojan (RAT), onto a system that is adequately protected with the Bit9 platform. Undaunted by this, the elite Hidden Lynx group took up the challenge. On February 8 2013, Bit9 released details revealing that a malicious third-party had gained access to one of their digital code-signing certificates. During this incident, a number of Trojans and malicious scripts were signed. In a follow up post on February 25, more details of the attack emerged. In July 2012, more than six months earlier, a malicious third-party gained access to their network using an SQL injection attack. Due to an operational oversight, a public-facing server that wasn’t protected with the Bit9 platform allowed the attackers to gain unauthorized access. The attackers installed Backdoor.Hikit, a Trojan that provides extremely stealthy remote access to compromised systems. This highly customized Trojan is typically installed onto servers in the victims’ DMZ, which was the case at Bit9. Credentials for another virtual machine were then stolen. These were used to access the virtual machine that contained one of Bit9’s digital code-signing certificates. The attackers used this code-signing infrastructure to sign thirty-two malicious files. Symantec telemetry shows some of these files have been present within select organizations in the United States defense industrial sector. The signing of these files is significant, since they could then be used to circumvent the trust protection model offered by the Bit9 platform. The Trojans signed include variants of Backdoor.Hikit (the remote access Trojan used in the initial compromise) and another RAT called Trojan.Naid. Some malicious attack scripts were also signed. Each Trojan has a specific purpose. Backdoor.Hikit was used to target public-facing infrastructure while Trojan. Naid was used to perform highly targeted attacks through email and watering-holes. Bit9 was alerted to the compromise in January 2013 and took immediate containment steps such as revoking the digital signature and reaching out to their entire customer base. According to Bit9, the attacks that followed Figure 3. Trojan.Naid – Bit9 digital certific ate, July 13, 2012, provided by Symantec’s CA Figure 4. Trojans successfully acquired with command-and- control (C&C) servers from the Bit9 investigation Page 10 Hidden Lynx – Professional Hackers for Hire were not financially motivated, but rather were an attempt to access information. On Bit9’s own admission, three customers were impacted. In conjunction with the Bit9 compromise, the Hidden Lynx group had another significant campaign well under way. They had just concluded phase one of the VOHO campaign, a watering-hole operation orchestrated to attack organizations in the Boston, Massachusetts area – it was a likely a distribution vector for the newly signed files. The VOHO campaign The VOHO campaign, first publicized by RSA, is one of the largest and most successful watering-hole attacks to date. The campaign combined both regional and industry-specific attacks and predominantly targeted organizations that operate in the United States. In a rapidly spreading two- phase attack, which started on June 25 and finished July 18, nearly 4,000 machines had downloaded a malicious payload. These payloads were being delivered to unsuspecting victims from legitimate websites that were strategically compromised. This watering-hole infection technique was quite innovative at the time. In a watering-hole attack, the attacker compromises a legitimate website that the target uses and trusts. The attacker then lies in wait for the target to visit the compromised site in order to infect them. The scale and targeted nature of the VOHO campaign set it apart from watering-hole attacks observed in the past. The group first adopted this technique in December 2011 when an exploit for the Oracle Java SE Rhino Script Engine Remote Code Execution Vulnerability (CVE-2011-3544) was leveraged to distribute their payloads. As a result of their success, many other strategic compromises have been adopted by other attack groups, as seen in a notable attack targeting iOS developers earlier in 2013 which impacted employees at Facebook, Apple and Twitter. In the VOHO campaign, ten legitimate websites were strategically compromised. The attackers carefully selected these websites based on the likelihood that the intended target(s) would visit them during the exploit delivery phase. The attackers likely pre-determined who visited the watering-hole in advance of the distribution phase of attack. This could easily be achieved by examining the access logs of compromised Web servers. The categories of websites compromised were both regional and industry-specific in nature and targeted the following key areas illustrated in Figure 5. Figure 5. The VOHO campaign target regions and industries Figure 6. The VOHO campaign malicious activity timeline - a two-phase attack Page 11 Hidden Lynx – Professional Hackers for Hire Timeline of activity The VOHO watering-hole distributed remote access Trojans in two phases. In phase one of the attack, an Internet Explorer zero-day vulnerability, the Microsoft XML Core Services CVE-2012-1889 Remote Code Execution Vulnerability (CVE-2012-1889), was leveraged. On July 10, Microsoft introduced the patch for CVE-2012-1889 and activity at the watering-hole ceased. This appears to have been a clever decision on behalf of the attackers. If they continued to deliver the exploit, they risked detection and would have hurt their chances of retaining access to the watering-hole for phase two of the campaign. Within six days, phase two of the distribution began, this time using a malicious Java applet exploiting the Oracle Java SE CVE-2012-1723 Remote Code Execution Vulnerability (CVE-2012-1723). This Java exploit was patched at the time. Having already used two zero-day exploits in quick succession (the first zero-day exploit was used in the GOTHAM campaign in May 2012, see appendix for more details), the Hidden Lynx group may not have had another one at their disposal. The timeline of activity at the watering-hole is shown in Figure 6. In each phase of the attack, two Trojans were being distributed at different intervals. The customized version of “Gh0st RAT”, Backdoor.Moudoor, saw large-scale distribution in comparison to Trojan.Naid, which was used more selectively in these attacks. Before being used in the second phase of the attack, Trojan.Naid was signed with the Bit9 certificate. Moudoor was never observed during the attack on Bit9, which could indicate that two separate teams are at work here. With Moudoor and Naid using different command-and-control (C&C) servers, each team could work independently on alternative objectives. The discovery of the Naid C&C would also be less likely in comparison to Moudoor’s, as its large-scale distribution would inevitably create more noise as it continued to impact many organizations. Figure 7. The VOHO campaign – Trojans distributed and C&C servers used to command and control Page 12 Hidden Lynx – Professional Hackers for Hire Team Naid’s role During this campaign, Team Naid had a very specific objective – to gain access to information from organizations operating in the defense industrial sector. An unsigned version of Naid was distribute