malware

Vidar Stealer Exploiting Various Platforms

Vidar Malware is one of the active Infostealers, and its distribution has been significantly increasing. Its characteristics include the use of famous platforms such as Telegram and Mastodon as an intermediary C2. The link below is a post about a case where malicious behaviors were performed using Mastodon. Even afterward, Vidar saw continuous version updates while actively being distributed. In the recent samples in circulation, various other platforms such as Steam and TikTok were used aside from Telegram and Mastodon….

ASEC Weekly Malware Statistics (December 5th, 2022 – December 11th, 2022)

The ASEC analysis team uses the ASEC automatic analysis system RAPIT to categorize and respond to known malware. This post will list weekly statistics collected from December 5th, 2022 (Monday) to December 11th, 2022 (Sunday). For the main category, downloader ranked top with 44.3%, followed by Infostealer with 28.2%, backdoor with 18.3%, ransomware with 8.5%, and CoinMiner with 0.7%. Top 1 – Amadey This week, Amadey Bot ranked first place with 15.9%. Amadey is a downloader that can receive commands…

Caution! Magniber Ransomware Restarts Its Propagation on December 9th With COVID-19 Related Filenames

On December 9th, 2022, the ASEC analysis team discovered that Magniber Ransomware is being distributed again. During the peak of the COVID-19 outbreak, Magniber was found being distributed with COVID-19 related filenames alongside the previous security update related filenames. C:\Users\$USERS\Downloads\COVID.Warning.Readme.2f4a204180a70de60e674426ee79673f.msiC:\Users\$USERS\Downloads\COVID.Warning.Readme.502ef18830aa097b6dd414d3c3edd5fb.msiC:\Users\$USERS\Downloads\COVID.Warning.Readme.a179a9245f8e13f41d799e775b71fdff.msi Table 1. COVID-19 related filenames in circulation In the past, Magniber exploited Internet Explorer’s vulnerability to infect user PCs via Drive by Download which only required users to visit a web page. However, after Microsoft stopped supporting Internet Explorer, Magniber’s…

ASEC Weekly Malware Statistics (November 28th, 2022 – December 4th, 2022)

The ASEC analysis team uses the ASEC automatic analysis system RAPIT to categorize and respond to known malware. This post will list weekly statistics collected from November 28th, 2022 (Monday) to December 4th, 2022 (Sunday). For the main category, Infostealer ranked top with 34.8%, followed by downloader with 28.2%, backdoor with 21.1%, ransomware with 14.6%, and CoinMiner with 0.3%. Top 1 – SmokeLoader SmokeLoader is an infostealer/downloader malware that is distributed via exploit kits. This week, it ranked first place with…

Malware Distributed with Disguised Filenames (RIGHT-TO-LEFT OVERRIDE)

In August, the ASEC analysis team made a post on the malware being distributed with filenames that utilize RTLO (Right-To-Left Override). RTLO is a unicode that makes an override from right to left. This type of malware induces users to execute its files by mixing filenames with extensions, with its distribution still being continued to this day. RAT Tool Disguised as Solution File (*.sln) Being Distributed on Github As of November 30th, 2022, when the keywords based on the last…