CyberSecurityNews

Ransomware Uses SYSTEM Scheduled Task to Encrypt Local Drives With Elevated Privileges


A newly analyzed ransomware strain called The Gentlemen is raising serious alarms across the cybersecurity community.

Built in the Go programming language and obfuscated with a tool called Garble, it combines powerful per-file encryption with an aggressive ability to spread itself silently across entire networks without any human intervention.

Organizations in education, healthcare, transportation, and finance across North America, South America, Europe, Africa, and Asia have already felt its damaging impact.

The Gentlemen operates as a ransomware-as-a-service (RaaS) platform, meaning its core developers rent access to the malware to other criminals known as affiliates.

It first emerged around mid-2025 as a closed group, then opened its doors to affiliates in September 2025.

More recently, its operators forged a formal partnership with BreachForums, a well-known cybercriminal marketplace, actively recruiting penetration testers and initial access brokers to carry out attacks on their behalf.

Microsoft Threat Intelligence, which tracks the group behind the malware as Storm-2697, noted that the operators use double extortion tactics.

Encryption mode command-line arguments (Source – Microsoft)

They encrypt a victim’s data and simultaneously steal sensitive files, threatening to release the stolen information publicly if the ransom is not paid.

Microsoft said in a report shared with Cyber Security News (CSN) that the threat is already widely adopted and this new partnership could attract an even broader pool of criminal actors going forward.

What sets The Gentlemen apart is its layered attack strategy. It disables antivirus tools, deletes backups, clears system logs, and wipes forensic traces before encryption even begins.

Once active, it can reach across a network and plant itself on other machines automatically, making containment far more difficult for incident responders and security teams.

The ransomware requires a build-specific password to execute, and operators can control nearly every aspect of its behavior through command-line arguments.

These options include setting encryption speed, enabling network spreading, and choosing how the malware persists after a reboot. That level of operational control makes it unusually flexible and customizable for a criminal tool deployed at scale.

Ransomware Uses SYSTEM Scheduled Task

One of the most technically notable behaviors in The Gentlemen is how it achieves the highest possible system privileges before encrypting local drives.

The Gentlemen ransomware’s persistence mechanism (Source - Microsoft)
The Gentlemen ransomware’s persistence mechanism (Source – Microsoft)

When the ransomware receives the right command-line instruction, it creates a Windows scheduled task named gentlemen_system that runs the malware executable under the SYSTEM account, which is the most powerful level of access on a Windows machine.

To do this cleanly, it first deletes any existing task with that name, then registers and immediately triggers a fresh one. Once running under this elevated context, the malware sets an internal environment variable called LOCKER_BACKGROUND=1 to signal that it is operating as a background encryption process with full privileges.

This design allows the ransomware to reach and encrypt files that would otherwise be protected or inaccessible to standard user-level accounts.

Self-Propagation Across the Network

The Gentlemen does not stop at a single machine. When its spreading feature is activated, it transforms into a self-propagating worm capable of deploying itself to every system it can reach on the local network.

It stages its own binary in a shared folder, copies it across administrative network shares, and attempts to execute it on remote hosts using eight different methods simultaneously.

These methods include PsExec, Windows Management Instrumentation, scheduled tasks in both user and SYSTEM contexts, Windows services, and PowerShell remoting.

The Gentlemen ransomware’s file encryption mechanism (Source - Microsoft)
The Gentlemen ransomware’s file encryption mechanism (Source – Microsoft)

The malware attempts 21 separate remote execution operations per target host. This redundancy is central to its strategy because even if most methods are blocked, a single successful execution on one new host is enough to restart the entire propagation cycle.

Defenders can reduce exposure by enabling controlled folder access, turning on cloud-delivered antivirus protection, and blocking process creations originating from PsExec and WMI commands through attack surface reduction rules.

Running endpoint detection and response tools in block mode is also strongly recommended, as is configuring automatic attack disruption to contain active threats before they spread further across the environment.

Indicators of Compromise (IoCs):-

TypeIndicatorDescription
SHA-25622b38dad7da097ea03aa28d0614164cd25fafeb1383dbc15047e34c8050f6f67The Gentlemen ransomware encryptor binary 
File NameREADME-GENTLEMEN.txtRansom note dropped in each encrypted directory 
File Extension.umc16hExtension appended to all encrypted files 
File Namegentlemen.bmpDesktop wallpaper bitmap dropped to %TEMP% after encryption 
Scheduled Task Namegentlemen_systemSYSTEM-privileged scheduled task created for elevated encryption 
Scheduled Task NameUpdateSystemPersistence scheduled task running payload as SYSTEM at startup 
Scheduled Task NameUpdateUserPersistence scheduled task running payload as current user at startup 
Registry Key ValueGupdateS (HKLM)System-wide autorun registry persistence key 
Registry Key ValueGupdateU (HKCU)User-scoped autorun registry persistence key 
File PathC:Temppsexec.exePsExec binary dropped for lateral movement 
File Namewipefile.tmpTemporary file used for free disk space wiping 
Environment VariableLOCKER_BACKGROUND=1Internal flag indicating SYSTEM-context background encryption execution 
Hardcoded Password9VoAvR7GBuild-specific operator authentication password embedded in analyzed sample 

Note: IP addresses and domains are intentionally defanged (e.g., [.]) to prevent accidental resolution or hyperlinking. Re-fang only within controlled threat intelligence platforms such as MISP, VirusTotal, or your SIEM.

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