Magniber

Rapidly Evolving Magniber Ransomware

The Magniber ransomware has recently been evolving rapidly. From changing its file extension, injection and to UAC bypassing techniques, the Magniber ransomware has been rapidly changing to bypass the detection of anti-malware software. This article summarizes the evolution of the Magniber ransomware in the last few months based on the analysis that had been previously performed. Table 1 shows the major characteristics of the distributed Magniber ransomware files by date. It had been distributed as five different file extensions (msi,…

Change in Magniber Ransomware (*.js → *.wsf) – September 28th

The ASEC analysis team has explained through the blog post on September 8th that the Magniber ransomware has changed from having a CPL extension to a JSE extension. The attacker made another change after September 8th, changing the file extension from JSE to JS on September 16th. And on September 28th, the attacker changed the distribution method once again, changing the file extension from JS to WSF. It seems the attacker is continuously distributing variations to bypass various detection methods…

Video of Blocking Latest Magniber Ransomware Using V3 (AMSI + Memory Scan)

The ASEC analysis team introduced the Magniber variants in the blog posted on September 15th. From September 16th, the Magniber ransomware script, whilst still a javascript, has its file extension changed from *.jse to *.js. As Magniber changed to javascript starting September 8th, its operational method has also changed from the previous method. The currently distributed javascript file contains a .NET DLL (see Figure 2), and injects the Magniber shell code into currently running processes. The overall operation flow of…

Magniber Disguised as Normal Windows Installer (MSI) Being Redistributed (February 22nd)

In the morning of February 22nd, the ASEC analysis team has discovered the redistribution of Magniber that disguised itself as normal Windows Installers (MSI) instead of the previous Windows app (APPX) The distributed Magniber files have MSI as their extension, disguised as Windows update files. Critical.Update.Win10.0-kb4215776.msi Critical.Update.Win10.0-kb6253668.msi Critical.Update.Win10.0-kb5946410.msi MSI package files are install frameworks that are also used for normal Windows updates. The malware was distributed by including the Magniber ransomware DLL within the MSI package file. By default, MSI…

Change in Magniber Ransomware Vulnerability (CVE-2021-40444)

Magniber is a fileless ransomware using an IE vulnerability and it is one of the ransomware that causes damage to numerous Korean users. It is difficult to prevent infection if not detected and blocked in advance during the vulnerability occurrence phase, which makes it difficult for anti-malware programs to detect it. Magniber ransomware had been distributed since March 15th, 2021 using CVE-2021-26411 vulnerability up to recently, but on September 16th, it was discovered that it changed to CVE-2021-40444 vulnerability. This…