THEGENTLEMEN Ransomware Gang: 15 Victims in a Single-Day Surge — Sector Analysis, CVE Correlation & Detection Rules

Classification: TLP:CLEAR | Report Date: 2026-08-15 | Source: ransomware.live monitoring of THEGENTLEMEN .onion leak site + CISA KEV correlation

Executive Summary

Security Arsenal dark web collection confirmed a 15-victim posting surge on 2026-08-14 to THEGENTLEMEN's leak site — the largest single-day dump we have observed from this crew in the current monitoring window. The campaign is indiscriminate by sector (technology, manufacturing, retail, healthcare, hospitality, professional services) but shows deliberate geographic spread across 8+ countries, consistent with an affiliate-driven RaaS model prioritizing volume over strategic targeting.

Most concerning: a US healthcare provider (First Coast Heart Vascular Center) and multiple small-to-mid-market businesses appear in the same posting wave, indicating the group is successfully monetizing low-maturity environments at scale. The CISA KEV additions of a Check Point Security Gateway authentication bypass (CVE-2026-50751) and ConnectWise ScreenConnect path traversal (CVE-2024-1708) align directly with the initial-access profile we attribute to this ecosystem.

Threat Actor Profile — THEGENTLEMEN

Analyst note: The mix of "Not Found" sector classifications (Acli, EKEPIS, TOA, Cityside Homes) indicates victims too small or too obscure for automated enrichment — a classic signature of opportunistic affiliate operations targeting organizations with weak external attack-surface hygiene.

Current Campaign Analysis

Sector Targeting (from live leak-site data)

Retail/e-commerce is overweighted — these organizations hold cardholder-adjacent data, POS-adjacent systems, and typically run lean security teams. The healthcare victim signals willingness to extort regulated entities where downtime pressure maximizes payment probability.

Geographic Concentration

BR (2), IT, US (2), GR, MA, MX, DE, JP, GB (2), MY, AU — no geographic focus whatsoever. This is a spray-and-monetize operation: affiliates compromise whatever their access vector yields, and the brand publishes everything. Latin America (BR/MX) and EMEA are both represented, matching the global footprint of edge-device scanning campaigns.

Victim Profile

Predominantly SMB-to-mid-market (estimated revenue $5M–$250M). Franchise operations (KFC Kosova), regional healthcare clinics, specialty retailers, and local manufacturers — organizations statistically least likely to have 24/7 SOC coverage, EDR on every endpoint, or immutable backups.

Posting Frequency / Escalation

15 posts in a single day against a recent-100 baseline of 19 indicates either (a) a burst of affiliate successes being batch-published for psychological impact, or (b) an extortion-deadline cascade where multiple negotiation windows expired simultaneously. Either way, expect follow-on waves in the next 7–14 days.

CVE Correlation — Probable Initial Access

The following CISA KEV entries (confirmed ransomware use) map directly onto this group's known access profile:

• CVE-2026-50751 — Check Point Security Gateway improper authentication (IKEv1 key exchange). Added to KEV 2026-06-08. This is the highest-priority correlation: VPN/security-gateway exploitation is the cleanest explanation for the simultaneous, geographically dispersed compromises of otherwise-unrelated SMBs. Any organization running Check Point gateways with IKEv1 enabled should treat themselves as pre-compromised until patched and hunted.
• CVE-2024-1708 — ConnectWise ScreenConnect path traversal → RCE. MSP/RMM abuse is a proven affiliate access vector and explains the breadth of small-business victims (who disproportionately rely on MSP-managed tooling).
• CVE-2025-60710 — Windows link-following privilege escalation and CVE-2023-21529 — Exchange deserialization: consistent with post-access privilege escalation and Exchange-side persistence in victim environments.
• CVE-2026-48027 — Nx Console embedded malicious code: a supply-chain angle targeting developer workstations — relevant to the technology-sector victims (Vector Two Technology).

Detection Engineering

The following detections target THEGENTLEMEN's affiliate playbook: edge/RMM initial access, macro execution, lateral movement via PsExec/WMI, and pre-encryption data staging.

---
title: THEGENTLEMEN - Suspect RMM or PsExec Service Execution for Lateral Movement
id: 8f3a2c1e-7b4d-4e9a-9c2f-thegent001a
status: experimental
description: Detects remote service creation/execution patterns used by THEGENTLEMEN affiliates for lateral movement, including PsExec-style service names and abused RMM tooling (ScreenConnect, AnyDesk, Atera) running from anomalous paths.
author: Security Arsenal Threat Intelligence
date: 2026/08/15
references:
  - https://securityarsenal.com/darkside
logsource:
  category: process_creation
  product: windows
detection:
  selection_psexec:
    Image|endswith:
      - '\PSEXESVC.exe'
      - '\psexec.exe'
      - '\paexec.exe'
  selection_rmm_anomalous:
    Image|endswith:
      - '\ScreenConnect.ClientService.exe'
      - '\AnyDesk.exe'
      - '\AteraAgent.exe'
    CommandLine|contains:
      - '\Temp\'
      - '\AppData\Local\Temp\'
      - '\ProgramData\'
      - '\Users\Public\'
  condition: 1 of selection_*
falsepositives:
  - Legitimate administrative use of PsExec or RMM; baseline approved RMM paths and service accounts
level: high
tags:
  - attack.lateral_movement
  - attack.t1569.002
  - attack.t1219
---
title: THEGENTLEMEN - Pre-Encryption Data Staging via Archive Utilities
id: 8f3a2c1e-7b4d-4e9a-9c2f-thegent002b
status: experimental
description: Detects mass-archive creation indicative of pre-exfiltration data staging observed before THEGENTLEMEN detonation. Flags rar/7z execution against document shares with password or multi-volume switches.
author: Security Arsenal Threat Intelligence
date: 2026/08/15
logsource:
  category: process_creation
  product: windows
detection:
  selection_binary:
    Image|endswith:
      - '\rar.exe'
      - '\7z.exe'
      - '\7za.exe'
      - '\winrar.exe'
  selection_args:
    CommandLine|contains:
      - ' a '
      - ' -p'
      - ' -v'
      - ' -r'
      - '\Shared'
      - '\Documents'
      - '*.doc*'
      - '*.xls*'
      - '*.pdf'
      - '*.sql'
      - '*.bak'
  condition: selection_binary and selection_args
falsepositives:
  - Legitimate backup jobs; whitelist known backup service accounts and scheduled windows
level: high
tags:
  - attack.collection
  - attack.t1560.001
---
title: THEGENTLEMEN - Shadow Copy Deletion and Recovery Inhibition Pre-Detonation
id: 8f3a2c1e-7b4d-4e9a-9c2f-thegent003c
status: experimental
description: Detects Volume Shadow Copy deletion and boot-recovery tampering executed minutes before ransomware encryption. High-fidelity T-minus indicator for THEGENTLEMEN playbook.
author: Security Arsenal Threat Intelligence
date: 2026/08/15
logsource:
  category: process_creation
  product: windows
detection:
  selection_vss:
    Image|endswith:
      - '\vssadmin.exe'
      - '\wmic.exe'
      - '\bcdedit.exe'
      - '\wbadmin.exe'
    CommandLine|contains:
      - 'delete shadows'
      - 'shadowcopy delete'
      - 'recoveryenabled no'
      - 'ignoreallfailures'
      - 'delete catalog'
  selection_ps:
    Image|endswith: '\powershell.exe'
    CommandLine|contains:
      - 'Get-WmiObject Win32_Shadowcopy'
      - 'Remove-WmiObject'
      - 'Win32_ShadowCopy.Delete'
  condition: 1 of selection_*
falsepositives:
  - Rare; some backup maintenance scripts. Investigate immediately regardless.
level: critical
tags:
  - attack.impact
  - attack.t1490

// THEGENTLEMEN Hunt — Pre-Ransomware Staging & Lateral Movement (Microsoft Sentinel)
// Hunt window: 14 days. Correlates archive staging, shadow-copy tampering, and
// suspicious remote service installs per device to surface T-minus activity.
let lookback = 14d;
let Staging =
    DeviceProcessEvents
    | where Timestamp > ago(lookback)
    | where FileName in~ ("rar.exe","7z.exe","7za.exe","winrar.exe")
    | where ProcessCommandLine has_any (" a "," -p"," -v"," -r")
       or ProcessCommandLine has_any (".doc",".xls",".pdf",".sql",".bak")
    | summarize StagingCount=count(), FirstStaging=min(Timestamp) by DeviceName, InitiatingProcessAccountName;
let ShadowTamper =
    DeviceProcessEvents
    | where Timestamp > ago(lookback)
    | where ProcessCommandLine has_any ("delete shadows","shadowcopy delete","recoveryenabled no","delete catalog","ignoreallfailures")
    | summarize TamperCount=count(), FirstTamper=min(Timestamp) by DeviceName;
let RemoteSvc =
    DeviceEvents
    | where Timestamp > ago(lookback)
    | where ActionType == "ServiceInstalled"
    | extend ServiceName = tostring(parse_json(AdditionalFields).ServiceName)
    | where ServiceName has_any ("PSEXESVC","ScreenConnect","AnyDesk","Atera","PAEXEC")
    | summarize RMMInstalls=count(), FirstInstall=min(Timestamp) by DeviceName;
Staging
| join kind=leftouter ShadowTamper on DeviceName
| join kind=leftouter RemoteSvc on DeviceName
| extend RiskScore = (StagingCount*2) + (coalesce(TamperCount,0)*10) + (coalesce(RMMInstalls,0)*5)
| where RiskScore >= 5
| project DeviceName, InitiatingProcessAccountName, StagingCount, TamperCount, RMMInstalls, FirstStaging, FirstTamper, RiskScore
| order by RiskScore desc;

# THEGENTLEMEN Rapid Triage — run on any suspect host (elevated)
# Checks: recent scheduled tasks (7d), shadow copy tampering signs, exposed RDP, suspicious services
Write-Host "=== THEGENTLEMEN Rapid Response Triage ===" -ForegroundColor Cyan

Write-Host "`n[1] Scheduled tasks created/modified in last 7 days:" -ForegroundColor Yellow
Get-ScheduledTask | Where-Object { $_.Date -and ([datetime]$_.Date) -gt (Get-Date).AddDays(-7) } |
  Select-Object TaskName, TaskPath, Date, @{N='RunAs';E={$_.Principal.UserId}} | Format-Table -AutoSize

Write-Host "`n[2] Volume Shadow Copies present (empty list = possible deletion):" -ForegroundColor Yellow
$shadows = Get-CimInstance Win32_ShadowCopy -ErrorAction SilentlyContinue
if ($shadows) { $shadows | Select-Object ID, InstallDate, DeviceObject | Format-Table -AutoSize }
else { Write-Host "  !! NO SHADOW COPIES FOUND — T-minus indicator, escalate immediately !!" -ForegroundColor Red }

Write-Host "`n[3] Recent vssadmin/bcdedit/wmic shadow-deletion events (Event 4680/Sysmon 1 context):" -ForegroundColor Yellow
Get-WinEvent -FilterHashtable @{LogName='Security'; Id=4680; StartTime=(Get-Date).AddDays(-7)} -ErrorAction SilentlyContinue |
  Where-Object { $_.Message -match 'vssadmin|bcdedit|wbadmin' } |
  Select-Object TimeCreated, Message -First 10 | Format-List

Write-Host "`n[4] RDP exposure check:" -ForegroundColor Yellow
$rdp = Get-ItemProperty 'HKLM:\SYSTEM\CurrentControlSet\Control\Terminal Server' -Name fDenyTSConnections -ErrorAction SilentlyContinue
if ($rdp.fDenyTSConnections -eq 0) { Write-Host "  RDP ENABLED — verify it is NOT reachable from the internet (3389)" -ForegroundColor Red }
else { Write-Host "  RDP disabled (good)" -ForegroundColor Green }
Get-NetTCPConnection -LocalPort 3389 -State Listen -ErrorAction SilentlyContinue | Format-Table LocalAddress, LocalPort, OwningProcess -AutoSize

Write-Host "`n[5] Suspicious services installed in last 7 days (PsExec/RMM pattern):" -ForegroundColor Yellow
Get-WinEvent -FilterHashtable @{LogName='System'; Id=7045; StartTime=(Get-Date).AddDays(-7)} -ErrorAction SilentlyContinue |
  Where-Object { $_.Message -match 'PSEXESVC|ScreenConnect|AnyDesk|Atera|PAEXEC|Temp|AppData|Users\\Public' } |
  Select-Object TimeCreated, Message | Format-List

Write-Host "`nTriage complete. Any red findings = isolate host from network immediately." -ForegroundColor Cyan

Incident Response Priorities

T-Minus Detection Checklist (BEFORE encryption fires)

1. Shadow copy deletion / bcdedit tampering — highest-fidelity indicator; typically 5–30 minutes before detonation. Any hit = isolate host NOW.
2. Mass archive creation (rar/7z with password switches) against file shares — data staging is active.
3. New RMM tools appearing on endpoints (ScreenConnect, AnyDesk, Atera) not in your approved software inventory.
4. PSEXESVC or Event 7045 service installs on servers from non-admin workstations.
5. Unusual outbound volume to cloud storage (Mega, Rclone to Backblaze/Dropbox) from servers — exfil in progress.
6. Check Point VPN log anomalies — IKEv1 authentication events from unexpected source IPs (CVE-2026-50751 probing).

Critical Assets Historically Prioritized for Exfiltration

• File servers / departmental shares (.doc, .xls, .pdf, .sql, .bak)
• Healthcare victims: patient records, imaging archives, billing data
• Financial data: payroll, banking credentials, tax documents
• Email archives from Exchange (correlates with CVE-2023-21529)
• HR/personnel records (leverage for secondary extortion of employees)

Containment Actions — Ordered by Urgency

1. Isolate affected hosts/segments at the switch or EDR level — do NOT power off (preserve memory evidence).
2. Disable VPN concentrator access if Check Point exploitation is suspected; force re-enrollment of all remote sessions.
3. Reset credentials for any account observed in staging/lateral movement telemetry — assume domain-level compromise if a DC was touched.
4. Block egress to known exfil destinations at the perimeter; capture DNS for C2 identification.
5. Kill RMM persistence — remove unauthorized remote tools and their service entries before rebuilding.
6. Snapshot forensic state (memory, triage image) before remediation on patient-zero host.

Hardening Recommendations

Immediate (24 hours)

• Patch Check Point Security Gateway for CVE-2026-50751 and disable IKEv1 if not operationally required. Audit VPN logs for the past 60 days.
• Patch ConnectWise ScreenConnect (CVE-2024-1708); if self-hosted and unpatched, take it offline and assume compromise.
• Inventory and block unauthorized RMM tools via application control (WDAC/AppLocker) — allow only your sanctioned platform.
• Verify RDP is not internet-exposed (3389) on any host; enforce VPN+MFA for all remote administration.
• Enable Office macro blocking from internet-sourced files (Mark of the Web) via GPO.
• Deploy the Sigma rules above to your SIEM and set the shadow-copy rule to page the on-call analyst.

Short-Term (2 weeks)

• Immutable/offline backups with restore testing — the only guaranteed recovery path against double extortion.
• Network segmentation isolating file servers, backup infrastructure, and OT/manufacturing segments from general user VLANs.
• Tiered administration model — no domain admin logons on workstations; dedicated PAWs for server management.
• Egress filtering and DLP on server subnets to catch bulk exfiltration before leak-site publication.
• Exchange hardening against CVE-2023-21529-class deserialization; restrict Exchange server outbound connectivity.
• Deploy deception (canary files/shares with alerting) on high-value file servers for early staging detection.
• Third-party/MSP audit — franchise and SMB victims in this wave suggest supply-chain reach through managed service providers.

Related Resources

Security Arsenal Incident Response Managed SOC & MDR Services AlertMonitor Threat Detection From The Dark Side Intel Hub