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RansomHouse upgrades encryption with multi-layered data processing. The RansomHouse ransomware-as-a-service (RaaS) has recently upgraded its encryptor, switching from a relatively simple single-phase linear technique to a more complex, multi-layered method. In practice, the upgrades offer stronger encryption results, faster speeds, and better reliability on modern target environments, giving threat actors stronger leverage during post-encryption negotiations. RansomHouse launched in December 2021 as a data extortion cybercrime operation, later adopting encryptors in attacks and developing an automated tool called MrAgent to lock multiple VMware ESXi hypervisors at once. Recently, it was reported that the threat actors used multiple ransomware families against the Japanese e-commerce giant Askul Corporation. A new report from researchers at Palo Alto Networks Unit 42 sheds more light on RansomHouse’s toolset, including its latest encryptor variant, dubbed ‘Mario.’ New ‘Mario’ encryptor RansomHouse’s latest encryptor variant switches from a single-pass file data transformation to a two-stage transformation that leverages two keys, a 32-byte primary and an 8-byte secondary key. This approach increases the encryption entropy and makes partial data recovery harder. The second major upgrade is the introduction of a new file processing strategy that uses dynamic chunk sizing at a threshold of 8GB, with intermittent encryption. Unit 42 says this makes static analysis more difficult due to its non-linearity, use of complex math to determine the processing order, and the use of distinct approaches for each file based on its size. Another notable upgrade in ‘Mario’ is the better memory layout and buffer organization, and higher complexity, with multiple dedicated buffers now used for each encryption stage or role. Finally, the upgraded encryptor version now prints more detailed information for file processing compared with the older variants, which only declared the task completion. The newer variant still targets VM files and renames the encrypted files with the ‘.emario’ extension, dropping a ransom note (How To Restore Your Files.txt) on all impacted directories. Unit 42 concludes that RansomHouse’s encryption upgrade is alarming, signaling “a concerning trajectory in ransomware development,” increasing the difficulty of decryption and making static analysis and reverse engineering harder. RansomHouse is one of the longer-running RaaS operations, but it remains mid-tier in terms of attack volume. Its continued development of advanced tooling suggests a calculated strategy focused on efficiency and evasion rather than scale. Break down IAM silos like Bitpanda, KnowBe4, and PathAI Broken IAM isn't just an IT problem - the impact ripples across your whole business. This practical guide covers why traditional IAM practices fail to keep up with modern demands, examples of what "good" IAM looks like, and a simple checklist for building a scalable strategy.

Daily Brief Summary

CYBERCRIME // RansomHouse Enhances Ransomware Capabilities with Advanced Encryption Techniques

RansomHouse, a ransomware-as-a-service group, has upgraded its encryption method, moving from a simple single-phase to a complex multi-layered approach, enhancing speed and reliability.

The new encryptor variant, named 'Mario,' employs a two-stage transformation using two distinct keys, complicating data recovery and increasing encryption entropy.

RansomHouse's latest strategy includes dynamic chunk sizing for files over 8GB, making static analysis challenging due to its non-linear processing and complex mathematical operations.

The upgraded encryptor improves memory layout and buffer organization, employing multiple dedicated buffers for each encryption stage, increasing complexity and hindering reverse engineering efforts.

The 'Mario' variant continues to target VMware ESXi hypervisors, renaming encrypted files with a '.emario' extension and deploying ransom notes across affected directories.

Palo Alto Networks Unit 42 warns that these advancements indicate a troubling trend in ransomware evolution, focusing on efficiency and evasion over sheer attack volume.

RansomHouse's sustained development of sophisticated tools suggests a strategic emphasis on enhancing negotiation leverage through stronger encryption capabilities.