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:
- 2020 Phishing Trends With PDF Files
April 5, 2021
From 2019-20, we noticed a dramatic 1,160% increase in malicious PDF files – from 411,800 malicious files to 5,224,056. PDF files are an enticing phishing vector as they are cross-platform and allow attackers to engage with users, making their schemes more believable as opposed to a text-based email with just a plain link. To lure users ...
- Ransomware gang leaks data from Stanford, Maryland universities
April 3, 2021
Personal and financial information stolen from Stanford Medicine, University of Maryland Baltimore (UMB), and the University of California was leaked online by the Clop ransomware group. The threat actors obtained the documents after hacking the universities’ Accellion File Transfer Appliance (FTA) software used to share and store sensitive information. Data stolen in the attack targeting Stanford Medicine’s ...
- FBI: APTs Actively Exploiting Fortinet VPN Security Holes
April 3, 2021
The FBI and the Cybersecurity and Infrastructure Security Agency are warning that advanced persistent threat (APT) nation-state actors are actively exploiting known security vulnerabilities in the Fortinet FortiOS cybersecurity operating system, affecting the company’s SSL VPN products. According to an alert issued Friday by the FBI and CISA, cyberattackers are scanning devices on ports 4443, 8443 ...
- Browser lockers: extortion disguised as a fine
April 2, 2021
Browser lockers (aka browlocks) are a class of online threats that prevent the victim from using the browser and demand a ransom. A locker is a fake page that dupes the user, under a fictitious pretext (loss of data, legal liability, etc.), into making a call or a money transfer, or giving out payment details. ...
- Hancitor’s Use of Cobalt Strike and a Noisy Network Ping Tool
April 1, 2021
Hancitor is an information stealer and malware downloader used by a threat actor designated as MAN1, Moskalvzapoe or TA511. In a threat brief from 2018, we noted Hancitor was relatively unsophisticated, but it would remain a threat for years to come. Approximately three years later, Hancitor remains a threat and has evolved to use tools ...
- USB threats to ICS systems have nearly doubled
April 1, 2021
The latest Honeywell USB Threat Report 2020 indicates that the number of threats specifically targeting Operational Technology systems has nearly doubled from 16% to 28%, while the number of threats capable of disrupting those systems rose from 26% to 59% over the same period. Let’s face it. Critical infrastructure operators in manufacturing, aerospace, energy, shipping, chemical, ...