The gaming industry keeps growing in terms of popularity, and the large population of gamers, and the crowds at Cologne's Gamescom 2014, represents an opportunity for miscreants to make money. In this blog post, we will explore various attacks specifically tailored to gamers, by starting with trojanized legitimate games, then by exploring some malicious software and targeted attacks against the video games industry. Finally, we will describe some recent exploits found in video games.

Gamescom 2014: Bitcoin Miners

Recent years have seen the introduction of Bitcoin, Dogecoin and other trendy and trending cryptographic currencies. These currencies are created by solving computationally-intensive cryptographic challenges, which require a lot of processing power. As gaming rigs are built with powerful processors and cutting-edge video cards, they can be considered one of the most efficient environments in which to “mine” these digital currencies, with the advantage of being widely spread among the Internet-using population.

In 2013, an employee of the ESEA Counter-Strike league silently introduced a Bitcoin miner into their anti-cheating software, which every member of the league had to install in order to participate. Fortunately the stratagem was uncovered rather quickly, and less than $4,000 worth of bitcoins were ‘earned’ by the malicious employee. More recently, a pirate version of the game 'WatchDogs' included a bitcoin mining Trojan which made a profit for the torrent’s author.

Keyloggers and Information Stealers

As the size of the gamer population has increased, some in-game goods have acquired some real monetary value. High-level/high-value characters, in-game currency, legendary items or even hats can be purchased with real money. But when something is worth money, it also means that for some people, it is worth stealing. Consequently, some malicious software focuses on stealing video games credentials. These information stealers are usually distributed under false pretenses, hiding behind so-called “game experience enhancers” or disguised as legitimate tools.

Keyloggers are the most prevalent type of malware in the gaming world, identified as Win32/PSW.OnLineGames by ESET. These programs can be pretty simple but have proven to be very effective at stealing players’ credentials, in order to resell items and characters. So many accounts are compromised that games editors are used to it and have implemented an FAQ and process to handle this situation.

To counter this type of malware, some MMORPG creators, such as Blizzard (who publish World Of Warcraft), have introduced two-factor authentication - and new titles introduced at Gamescom 2014 will do the same. This two-factor authentication takes the form of an electronic device (or a smartphone application) delivering unique six-digit codes that are active and valid only for a limited time before a new code has to be generated.

At the beginning of this year, malicious software named Disker was able to bypass this double-authentication mechanism. Disker appears to be as complex as malicious software that focuses on stealing banking information and it has the ability to steal both the victim’s account credentials and his or her authenticating six-digit passcode.

But as the passcode remains valid only for a short period of time, the attacker has to be behind his keyboard when the information is exfiltrated so as to be able to use it. So Disker implements a way to circumvent this problem: as it leaks the 6-digit passcode to the attacker, it will actually send a wrong passcode to the World Of Warcraft server, preventing the user from logging in. At this point, the victim will almost certainly disable the two-factor authentication in order to enjoy his game. Once this is done, the attacker is no longer restricted to operating within a short period of time.

Targeted Attacks

Players are not the only target in the gaming ecosystem, games companies can also be specifically attacked. For example Kaspersky discovered last year a malware targeting no less than 30 MMORPG game companies. In this case the attack was intended to:

1. Deploy malware on gamers’ computers by using the MMORPG update server
2. Manipulate in-game currencies
3. Steal digital-certificate to create signed-malware, making the malware easier to propagate
4. Steal the MMORPG source code to deploy it on rogue servers

Exploits

MMORPGs are not the only targeted type of games, other kinds of multiplayer games are also potential targets. Recently, security researchers Luigi Auriemma and Donato Ferrante have been looking for vulnerabilities in games and game engines.

The results are impressive: they found vulnerabilities in the Source Engine, making any game based on this engine vulnerable, such as the famous Counter-Strike Source, Team Fortress 2 and Left 4 Dead. Those vulnerabilities could be used to execute code on a player’s computer without their knowledge and consent, potentially leading to installation of malware without requiring any action from the user other than his usual gaming activity.

Today, no known malware spreads using vulnerabilities in games but the rising value of in-game goods could motivate malicious people enough to use this kind of attack to spread game-targeted malware.

Conclusion

The emergence of such malware shows that the high value of in-game goods is appealing to bad guys - and the titles shown at Gamescom 2014 will be high-value targets.

The complexity of these types of malware, and the implementation by Blizzard of protective measures similar to those used by banks, indicate that we are at the beginning of an arms race between criminals and the gaming world. In this race, everyone has a role to play, editors by securing players’ accounts adequately, and players by educating themselves about the dangers, the existing solutions, and how to behave in order to enjoy safer gaming.