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:
- Critical Microsoft Hyper-V bug could haunt orgs for a long time
July 28, 2021
Technical details are now available for a vulnerability that affects Hyper-V, Microsoft’s native hypervisor for creating virtual machines on Windows systems and in the Azure cloud computing environment. Currently tracked as CVE-2021-28476, the security issue has a critical severity score of 9.9 out of 10. Exploiting it on unpatched machines can have a devastating impact as ...
- DDoS attacks in Q2 2021
July 28, 2021
In terms of big news, Q2 2021 was relatively calm, but not completely eventless. For example, April saw the active distribution of a new DDoS botnet called Simps — the name under which it introduced itself to owners of infected devices. The malware creators promoted their brainchild on a specially set-up YouTube channel and Discord ...
- THOR: Previously Unseen PlugX Variant Deployed During Microsoft Exchange Server Attacks by PKPLUG Group
July 27, 2021
While monitoring the Microsoft Exchange Server attacks in March 2021, Unit 42 researchers identified a PlugX variant delivered as a post-exploitation remote access tool (RAT) to one of the compromised servers. The variant observed by Unit 42 is unique in that it contains a change to its core source code: the replacement of its trademark ...
- UC San Diego Health discloses data breach after phishing attack
July 27, 2021
UC San Diego Health, the academic health system of the University of California, San Diego, has disclosed a data breach after the compromise of some employees’ email accounts. UC San Diego Health is one of the nation’s best hospitals, being repeatedly ranked as the best health care system in San Diego, according to the 2021-2022 U.S. ...
- Threat Actors Exploit Misconfigured Apache Hadoop YARN
July 27, 2021
The misconfiguration and resulting exposure of cloud services is one of the most prevalent risks in the Linux threat landscape. We previously analyzed incidents related to this security concern, such as an exposed Docker API being abused by threat actors in the wild and exposed Redis instances that threat actors actively search. This blog post will ...
- LockBit ransomware now encrypts Windows domains using group policies
July 27, 2021
A new version of the LockBit 2.0 ransomware has been found that automates the encryption of a Windows domain using Active Directory group policies. The LockBit ransomware operation launched in September 2019 as a ransomware-as-a-service, where threat actors are recruited to breach networks and encrypt devices. In return, the recruited affiliates earn 70-80% of a ransom payment, ...