The financially motivated risk actor often called Storm-0501 has been noticed refining its ways to conduct information exfiltration and extortion assaults focusing on cloud environments.
“Not like conventional on-premises ransomware, the place the risk actor usually deploys malware to encrypt essential information throughout endpoints throughout the compromised community after which negotiates for a decryption key, cloud-based ransomware introduces a basic shift,” the Microsoft Risk Intelligence group mentioned in a report shared with The Hacker Information.
“Leveraging cloud-native capabilities, Storm-0501 quickly exfiltrates giant volumes of knowledge, destroys information and backups throughout the sufferer surroundings, and calls for ransom — all with out counting on conventional malware deployment.”
Storm-0501 was first documented by Microsoft virtually a 12 months in the past, detailing its hybrid cloud ransomware assaults focusing on authorities, manufacturing, transportation, and regulation enforcement sectors within the U.S., with the risk actors pivoting from on-premises to cloud for subsequent information exfiltration, credential theft, and ransomware deployment.
Assessed to be energetic since 2021, the hacking group has advanced right into a ransomware-as-a-service (RaaS) affiliate delivering numerous ransomware payloads through the years, resembling Sabbath, Hive, BlackCat (ALPHV), Hunters Worldwide, LockBit, and Embargo.
“Storm-0501 has continued to show proficiency in shifting between on-premises and cloud environments, exemplifying how risk actors adapt as hybrid cloud adoption grows,” the corporate mentioned. “They hunt for unmanaged gadgets and safety gaps in hybrid cloud environments to evade detection and escalate cloud privileges and, in some circumstances, traverse tenants in multi-tenant setups to realize their objectives.”
Typical assault chains contain the risk actor abusing their preliminary entry to realize privilege escalation to a site administrator, adopted by on-premises lateral motion and reconnaissance steps that permit the attackers to breach the goal’s cloud surroundings, thereby initiating a multi-stage sequence involving persistence, privilege escalation, information exfiltration, encryption, and extortion.
Preliminary entry, per Microsoft, is achieved via intrusions facilitated by entry brokers like Storm-0249 and Storm-0900, making the most of stolen, compromised credentials to check in to the goal system, or exploiting numerous identified distant code execution vulnerabilities in unpatched public-facing servers.
In a current marketing campaign focusing on an unnamed giant enterprise with a number of subsidiaries, Storm-0501 is alleged to have carried out reconnaissance earlier than laterally shifting throughout the community utilizing Evil-WinRM. The attackers additionally carried out what’s known as a DCSync Assault to extract credentials from Energetic Listing by simulating the habits of a site controller.
“Leveraging their foothold within the Energetic Listing surroundings, they traversed between Energetic Listing domains and ultimately moved laterally to compromise a second Entra Join server related to a unique Entra ID tenant and Energetic Listing area,” Microsoft mentioned.
“The risk actor extracted the Listing Synchronization Account to repeat the reconnaissance course of, this time focusing on identities and sources within the second tenant.”
These efforts finally enabled Storm-0501 to determine a non-human synced id with a International Admin position in Microsoft Entra ID on that tenant, and missing in multi-factor authentication (MFA) protections. This subsequently opened the door to a situation the place the attackers reset the consumer’s on-premises password, inflicting it to be synced to the cloud id of that consumer utilizing the Entra Join Sync service.
Armed with the compromised International Admin account, the digital intruders have been discovered to entry the Azure Portal, registering a risk actor-owned Entra ID tenant as a trusted federated area to create a backdoor, after which elevate their entry to essential Azure sources, earlier than setting the stage for information exfiltration and extortion.
“After finishing the exfiltration section, Storm-0501 initiated the mass-deletion of the Azure sources containing the sufferer group information, stopping the sufferer from taking remediation and mitigation motion by restoring the information,” Microsoft mentioned.
“After efficiently exfiltrating and destroying the information throughout the Azure surroundings, the risk actor initiated the extortion section, the place they contacted the victims utilizing Microsoft Groups utilizing one of many beforehand compromised customers, demanding ransom.”
The corporate mentioned it has enacted a change in Microsoft Entra ID that forestalls risk actors from abusing Listing Synchronization Accounts to escalate privileges. It has additionally launched updates to Microsoft Entra Join (model 2.5.3.0) to assist Trendy Authentication to permit prospects to configure application-based authentication for enhanced safety.
“It’s also essential to allow Trusted Platform Module (TPM) on the Entra Join Sync server to securely retailer delicate credentials and cryptographic keys, mitigating Storm-0501’s credential extraction methods,” the tech large added.
