Resource

What is REvil ransomware?

Sodinokibi aka REvil Ransomware explained

What is REvil Ransomware?

REvil ransomware is a file blocking virus considered a serious threat that encrypts files after infection and discards a ransom request message. The message explains that the victim needs to pay a ransom in bitcoins and that when the ransom is not paid in time the demand doubles.

McAfee’s Advanced Threat Research team (ATR) observed the new ransomware family in the wild, dubbed Sodinokibi (or REvil), at the end of April 2019. 

The name Sodinokibi was discovered in the hash ccfde149220e87e97198c23fb8115d5a where ‘Sodinokibi.exe’ was mentioned as the internal file name; it is also known by the name of REvil.

REvil: Ransomware-as-a-Service

At first, REvil ransomware was observed propagating itself by exploiting a vulnerability in Oracle’s WebLogic server. Similar to some other ransomware families however, REvil is what is also called a Ransomware-as-a-Service (RaaS). Ransomware-as-a-Service is where a group of people maintain the code and another group, known as affiliates, spread the ransomware.

Such a RaaS model allows affiliates to distribute REvil ransomware in any way they want, such as mass-spread attacks using exploit-kits and phishing-campaigns , where other affiliates adopt a more targeted approach by uploading tools and scripts to gain more rights and execute the ransomware in the internal network of a victim or brute-forcing RDP access. McAfee has investigated several campaigns spreading REvil, most of which had different modus operandi but they did notice many started with a breach of an RDP server. McAfee also revealed that the code part responsible for the random URL generation of REvil ransomware has similarities with regards to how it is generated in the GandCrab malware.

According to McAfee 'overall the code is very well written and designed to execute quickly to encrypt the defined files in the configuration of the ransomware.'

Based on the code comparison analysis McAfee conducted between GandCrab and Sodinokibi McAfee consider it a likely hypothesis that the people behind the Sodinokibi ransomware may have some type of relationship with the GandCrab crew.

REvil Ransomware Functionalities

REvil ransomware world map overview

Based on visibility from McAfee's MVISION Insights, McAfee was able to generate a overview map of REvil ransomware infections observed from May through August 23rd, 2019:

Detecting REvil Ransomware

McAfee is detecting this family by the following signatures:

“Ransom-Sodinokibi”
“Ransom-REvil!”.

MITRE ATT&CK Techniques

The malware sample uses the following MITRE ATT&CK™ techniques:

File and Directory Discovery
File Deletion
Modify Registry
Query Registry
Registry modification
Query information of the user
Crypt Files
Destroy Files
Make C2 connections to send information of the victim
Modify system configuration
Elevate privileges

YARA Rule

rule Sodinokobi 

{

/*

This rule detects Sodinokobi Ransomware in memory in old samples and perhaps future.

*/

meta:

author      = “McAfee ATR team”

version     = “1.0”

description = “This rule detect Sodinokobi Ransomware in memory in old samples and perhaps future.”

strings:

$a = { 40 0F B6 C8 89 4D FC 8A 94 0D FC FE FF FF 0F B6 C2 03 C6 0F B6 F0 8A 84 35 FC FE FF FF 88 84 0D FC FE FF FF 88 94 35 FC FE FF FF 0F B6 8C 0D FC FE FF FF }

$b = { 0F B6 C2 03 C8 8B 45 14 0F B6 C9 8A 8C 0D FC FE FF FF 32 0C 07 88 08 40 89 45 14 8B 45 FC 83 EB 01 75 AA }

condition:

all of them

}

Protecting against REvil Ransomware/Sodinokibi

To protect your organization against Sodinokibi, make sure your defense is layered. The actors either buy, brute-force or spear-phish themselves into your company or use a trusted-third party that has access to your network. Some guidelines for organizations to protect themselves include employing sandboxing, backing up data, educating users, and restricting access.

Talk with an Expert

Speak with an industry expert. Give us a call or leave a message. Our team is ready for your business.

Infradata is an award-winning McAfee Enterprise Partner and reseller. Our seasoned engineers deliver premium support and can execute projects on any scale.

Share this page:

This site uses cookies. By continuing to browse the site you are agreeing to our use of cookies. Find out more here.