Attackers typically try to pass off malware as legitimate applications or as potentially unwanted programs that users deliberately search for and download, such as cheats or cracks. They often rely on ad and affiliate networks to deliver their creations to victims’ devices. This post examines a less conventional case: a well-known backdoor distributed under the guise of adware. The attackers may have chosen this distribution method because the adware was signed by the developer. On top of that, users often manually add these apps to exclusions, so their useful features don’t get blocked.
Some time ago, a client asked us to analyze a file with the MD5 hash c24e99f9437feacaa63766a3cde3fe3d and add it to our detection database. We initially classified it as adware, but a cursory analysis turned up suspicious network activity, which prompted us to dig deeper. It turned out the sample did far more than serve ads. In fact, its advertising functionality doesn’t even work; instead, it triggers an infection chain that delivers the ValleyRAT backdoor.
Read more…
Source: Kaspersky
Sign up for the Cyber Security Review Newsletter
The latest cyber security news and insights delivered right to your inbox
Related:
- DDoS Attacks and IoT Exploits: New Activity from Momentum Botnet
December 16, 2019
Trend Micro recently found notable malware activity affecting devices running Linux, a platform that has battled numerous issues just this year. Further analysis of retrieved malware samples revealed that these actions were connected to a botnet called Momentum (named for the image found in its communication channel). We found new details on the tools and techniques ...
- Mirai Variant ECHOBOT Resurfaces with 13 Previously Unexploited Vulnerabilities
December 13, 2019
Since the discovery of the Mirai variant using the binary name ECHOBOT in May 2019, it has resurfaced from time to time, using new infrastructure, and more remarkably, adding to the list of vulnerabilities it scans for, as a means to increase its attack surface with each evolution. Unlike other Mirai variants, this particular variant stands out for the sheer ...
- Multi-stage downloader Trojan sLoad abuses BITS almost exclusively for malicious activities
December 12, 2019
Many of today’s threats evolve to incorporate as many living-off-the-land techniques as possible into the attack chain. The PowerShell-based downloader Trojan known as sLoad, however, puts all its bets on BITS. Background Intelligent Transfer Service (BITS) is a component of the Windows operating system that provides an ability to transfer files in an asynchronous and throttled fashion using ...
- More than a Dozen Obfuscated APT33 Botnets Used for Extreme Narrow Targeting
December 12, 2019
The threat group regularly referred to as APT33 is known to target the oil and aviation industries aggressively. This threat group has been reported on consistently for years, but our recent findings show that the group has been using about a dozen live Command and Control (C&C) servers for extremely narrow targeting. The group puts up multiple layers of obfuscation to ...
- DeCypherIT – All eggs in one basket
December 12, 2019
These days, attackers use cheap and publicly accessible services to help them bypass Anti-Virus protections and gain a foothold in their victims’ systems. We give a behind the scenes look at a service called CypherIt, which is sold publicly as a legitimate service but is used to wrap malwares and hide their malicious content. This evasion technique ...
- Zeppelin: Russian Ransomware Targets High Profile Users in the U.S. and Europe
December 11, 2019
Zeppelin is the newest member of the Delphi-based Ransomware-as-a-Service (RaaS) family initially known as Vega or VegaLocker. Although it’s clearly based on the same code and shares most of its features with its predecessors, the campaign that it’s been part of differs significantly from campaigns involving the previous versions of this malware. Vega samples were first ...