T1490: Inhibit System Recovery

Medusa Group has been active since at least 2021 and was initially operated as a closed ransomware group before evolving into a Ransomware-as-a-Service (RaaS) operation. Some reporting indicates that certain attacks may still be conducted directly by the ransomware’s core developers. Public sources have also referred to the group as “Spearwing” or “Medusa Actors.” [1] [2] Medusa Group employs living-off-the-land techniques, frequently leveraging publicly available tools and common remote management software to conduct operations. The group engages in double extortion tactics, exfiltrating data prior to encryption and threatening to publish stolen information if ransom demands are not met. [3] For initial access, Medusa Group has exploited publicly known vulnerabilities, conducted phishing campaigns, and used credentials or access purchased from Initial Access Brokers (IABs). The group is opportunistic and has targeted a wide range of sectors globally. [4]

Storm-0501 is a financially motivated cyber criminal group that uses commodity and open-source tools to conduct ransomware operations. Storm-0501 has been active since 2021 and has previously been affiliated with Sabbath Ransomware and other Ransomware-as-a-Service (RaaS) variants such as Hive, BlackCat, Hunters International, LockBit 3.0, and Embargo ransomware.[1][2][3][4]

VOID MANTICORE is a threat group assessed to operate on behalf of Iran’s Ministry of Intelligence and Security (MOIS).[1] Active since at least mid-2022, VOID MANTICORE has targeted government entities, critical infrastructure, and private sector organizations across Albania, Israel, and the United States.[1][2] VOID MANTICORE conducts destructive cyber operations, combining wiper attacks with hack-and-leak campaigns. The group has operated under multiple public-facing personas, including HomeLand Justice in operations against Albania, Karma and Karma Below in campaigns targeting Israeli organizations, and Handala Hack, its current primary persona, which has claimed activity against Israeli and U.S. entities, including a March 2026 attack against Stryker Corporation.[1][3] VOID MANTICORE has been observed collaborating with Scarred Manticore, which has been linked to initial access operations preceding VOID MANTICORE’s activity.[4]

Wizard Spider is a Russia-based financially motivated threat group originally known for the creation and deployment of TrickBot since at least 2016. Wizard Spider possesses a diverse arsenal of tools and has conducted ransomware campaigns against a variety of organizations, ranging from major corporations to hospitals.[1][2][3]

BlackByte is a ransomware threat actor operating since at least 2021. BlackByte is associated with several versions of ransomware also labeled BlackByte Ransomware. BlackByte ransomware operations initially used a common encryption key allowing for the development of a universal decryptor, but subsequent versions such as BlackByte 2.0 Ransomware use more robust encryption mechanisms. BlackByte is notable for operations targeting critical infrastructure entities among other targets across North America.[1][2][3][4][5]

Scattered Spider is a native English-speaking cybercriminal group active since at least 2022. [1] [2] The group initially targeted customer relationship management (CRM) providers, business process outsourcing (BPO) firms, and telecommunications and technology companies before expanding in 2023 to gaming, hospitality, retail, managed service provider (MSP), manufacturing, and financial sectors. [2] Scattered Spider relies heavily on social engineering, including impersonating IT and help-desk staff, to gain initial access, bypass multi-factor authentication (MFA), and compromise enterprise networks. The group has adapted its tooling to evade endpoint detection and response (EDR) defenses and used ransomware for financial gain. [3] [4] [5] Scattered Spider had expanded into hybrid cloud and identity environments, using help-desk impersonation and MFA bypass to obtain administrator access in Okta, AWS, and Office 365. [6]

Sandworm Team is a destructive threat group that has been attributed to Russia's General Staff Main Intelligence Directorate (GRU) Main Center for Special Technologies (GTsST) military unit 74455.[1][2] This group has been active since at least 2009.[3][4][5][6]

In October 2020, the US indicted six GRU Unit 74455 officers associated with Sandworm Team for the following cyber operations: the 2015 and 2016 attacks against Ukrainian electrical companies and government organizations, the 2017 worldwide NotPetya attack, targeting of the 2017 French presidential campaign, the 2018 Olympic Destroyer attack against the Winter Olympic Games, the 2018 operation against the Organisation for the Prohibition of Chemical Weapons, and attacks against the country of Georgia in 2018 and 2019.[1][2] Some of these were conducted with the assistance of GRU Unit 26165, which is also referred to as APT28.[7]

Black Basta is ransomware written in C++ that has been offered within the ransomware-as-a-service (RaaS) model since at least April 2022; there are variants that target Windows and VMWare ESXi servers. Black Basta operations have included the double extortion technique where in addition to demanding ransom for decrypting the files of targeted organizations the cyber actors also threaten to post sensitive information to a leak site if the ransom is not paid. Black Basta affiliates have targeted multiple high-value organizations, with the largest number of victims based in the U.S. Based on similarities in TTPs, leak sites, payment sites, and negotiation tactics, security researchers assess the Black Basta RaaS operators could include current or former members of the Conti group.[1][2][3][4][5][6]

Ragnar Locker is a ransomware that has been in use since at least December 2019.[1][2]

InvisiMole is a modular spyware program that has been used by the InvisiMole Group since at least 2013. InvisiMole has two backdoor modules called RC2FM and RC2CL that are used to perform post-exploitation activities. It has been discovered on compromised victims in the Ukraine and Russia. Gamaredon Group infrastructure has been used to download and execute InvisiMole against a small number of victims.[1][2]

Playcrypt is a ransomware that has been used by Play since at least 2022 in attacks against against the business, government, critical infrastructure, healthcare, and media sectors in North America, South America, and Europe. Playcrypt derives its name from adding the .play extension to encrypted files and has overlap with tactics and tools associated with Hive and Nokoyawa ransomware and infrastructure associated with Quantum ransomware.[1][2][3]

WastedLocker is a ransomware family attributed to Indrik Spider that has been used since at least May 2020. WastedLocker has been used against a broad variety of sectors, including manufacturing, information technology, and media.[1][2][3]

H1N1 is a malware variant that has been distributed via a campaign using VBA macros to infect victims. Although it initially had only loader capabilities, it has evolved to include information-stealing functionality. [1]

RobbinHood is ransomware that was first observed being used in an attack against the Baltimore city government's computer network.[1][2]

Ryuk is a ransomware designed to target enterprise environments that has been used in attacks since at least 2018. Ryuk shares code similarities with Hermes ransomware.[1][2][3]

DarkWatchman is a lightweight JavaScript-based remote access tool (RAT) that avoids file operations; it was first observed in November 2021.[1]

Medusa Ransomware has been utilized in attacks since at least 2021. Medusa Ransomware has been known to be utilized in conjunction with living off the land techniques and remote management software. Medusa Ransomware has been used in campaigns associated with “double extortion” ransomware activity, where data is exfiltrated from victim environments prior to encryption, with threats to publish files if a ransom is not paid. Medusa Ransomware software was initially a closed ransomware variant which later evolved to a Ransomware as a Service (RaaS). Medusa Ransomware has impacted victims from a diverse range of sectors within a multitude of countries, and it is assessed Medusa Ransomware is used in an opportunistic manner.[1][2][3][4]

EKANS is ransomware variant written in Golang that first appeared in mid-December 2019 and has been used against multiple sectors, including energy, healthcare, and automotive manufacturing, which in some cases resulted in significant operational disruptions. EKANS has used a hard-coded kill-list of processes, including some associated with common ICS software platforms (e.g., GE Proficy, Honeywell HMIWeb, etc), similar to those defined in MegaCortex.[1][2]

INC Ransomware is a ransomware strain that has been used by the INC Ransom group since at least 2023 against multiple industry sectors worldwide. INC Ransomware can employ partial encryption combined with multi-threading to speed encryption.[1][2][3]

2025 Poland Wiper Attacks is a Russian state-sponsored campaign that conducted destructive cyberattacks against Polish energy infrastructure in December 2025. Targets included more than 30 wind and photovoltaic farms, a combined heat and power (CHP) plant, and a manufacturing sector company. The attacks on the distributed energy resources (DER) disrupted communications between affected facilities and the distribution system operator, but did not impact electricity generation or heat supply. Across the campaign, threat actors deployed two previously undocumented wiper tools, DynoWiper, a Windows-based wiper and LazyWiper, a PowerShell wiper, distributed via malicious Group Policy Objects. At the CHP plant, threat actors had maintained access since at least March 2025, using that foothold to obtain credentials and move laterally before attempting wiper deployment. Some reporting has assessed the activity to be consistent with Russian Federal Security Service (FSB) threat activity group Dragonfly, also tracked as STATIC TUNDRA, while other reporting attributes the destructive wiper activities to the Russian General Staff Main Intelligence Directorate (GRU) threat activity group ELECTRUM, also tracked as Sandworm Team.[1][2][3][4]