Romanian Water & Energy Authorities Ransomware Attacks
BLUF
Ransomware attacks targeting Romanian critical infrastructure entities, specifically the national water management agency and a major energy producer, encrypting systems and demanding ransom.
Executive Cost Summary
This cost analysis was developed by the CyberDax team using expert judgment and assisted analytical tools to support clarity and consistency.
For organizations affected by ransomware activity targeting critical water and energy infrastructure:
Low-end total cost: $2.5M – $3.5M
(Rapid containment, limited system spread, strong backups)Typical expected range: $4M – $6.5M
Upper-bound realistic scenarios: $7M – $10M
(Extended outages, regulatory escalation, and multi-site recovery)
Key cost driver:
Prolonged operational disruption in essential services rather than ransom demand size
Regulatory and government oversight obligations unique to critical infrastructure
Complexity of restoring trust in OT and hybrid IT/OT environments after encryption events
Long-tail insurance and compliance costs extending well beyond technical recovery
Targeted Sectors
· Critical Infrastructure
o Water Management
o Energy/Power Production
Countries
· Romania
Date of First Reported Activity
· January 5, 2026
Date of Last Reported Activity Update
· January 5, 2026
APT Names
· None confirmed
Associated Criminal Organization Names
· Gentlemen group
o Attributed to the energy producer attack
IOCs
· System outages
· Encrypted files
· Ransom notes
Tools Used in Campaign
· Windows' BitLocker tool
o Used for encryption
· Possibly a new strain of "Gentlemen" ransomware.
CVEs and CVSS Vectors
· Not mentioned in open-source reporting
Nessus ID
· Not mentioned in open-source reporting
Mitigation Data
Follow general ransomware best practices
· Segment networks
· Implement strong access controls
· Ensure secure backups
· Apply zero-trust principles
Malware Names
· Gentlemen ransomware
· BitLocker (abused legitimate tool).
Malware Samples
As a reminder the heuristic behavior of the malware should be what is hunted on. hashes, domains, etc. tend to be dynamic and will usually be different for each target, attack and can be different within the same attack
README-GENTLEMEN.zip
sha256
f8b07ce20ae77fec0905724a466196a5ba8281e9ba9534808ab7e7bf15f37516
URL link to sample
· hxxps://bazaar.abuse.ch/sample/f8b07ce20ae77fec0905724a466196a5ba8281e9ba9534808ab7e7bf15f37516/
queen-charlie-connecticut-friend
sha256
51b9f246d6da85631131fcd1fabf0a67937d4bdde33625a44f7ee6a3a7baebd2
URL link to sample
hxxps://bazaar.abuse.ch/sample/51b9f246d6da85631131fcd1fabf0a67937d4bdde33625a44f7ee6a3a7baebd2/
TTPs
TA0001 Initial Access
· T1078.002 Valid Accounts: Compromised Accounts
· T1190 Exploit Public-Facing Application: Exploiting internet-exposed services or vulnerable VPNs/RDP
TA0007 Discovery:
· T1018 Remote System Discovery
· T1046 Network Service Scanning: Use of tools like Advanced IP Scanner to map the network
· T1082 System Information Discovery
· T1087.002 Account Discovery: Privileged Account Discovery
· T1482 Domain Trust Discovery
TA0004 Privilege Escalation
· T1078.002 Valid Accounts: Use of compromised domain administrator accounts for maximum impact
· Abuse of legitimate drivers for kernel-level manipulation to terminate security processes
TA0008 Lateral Movement:
· T1021.001 Remote Desktop Protocol
· T1021.004 Remote Services: Use of administrative tools for spreading across the network
TA0005 Defense Evasion:
· T1562.001 Impair Defenses: Disabling security software and stopping database/backup services
· T1112 Modify Registry
· T1027 Obfuscated Files or Information
· T1001.001 Data Obfuscation: Encrypted communication channels for command and control (C2)
TA0010 Exfiltration
(Part of a double-extortion strategy)
· T1048.001 Exfiltration Over C2 Channel
· T1041 Exfiltration Over Other Network Medium
TA0040 Impact
· T1486 Data Encrypted for Impact: Primary use of encryption to deny access
· T1489 Service Stop: Stopping services to facilitate encryption and disrupt operations
· T1490 Inhibit System Recovery: Targeting backups and system recovery functions
· T1059.001 Command and Scripting Interpreter: Use of PowerShell for execution and persistence
· T1562.004 Disable or Modify System Firewall
· T1053.005 Scheduled Task/Job: Scheduled Task (for persistence)
Suggested Rules / potential hunts
As a reminder, these are indicator rules. They are likely to be noisy.
For best results consider creating a data model and reviewing the traffic as a report.
Suricata
Gentlemen Ransomware C2 Traffic
alert tcp $HOME_NET any -> $EXTERNAL_NET any (msg:"ET RANSOMWARE Gentlemen Ransomware C2 Communication Attempt"; flow:established,to_server; content:"POST"; http_uri; content:"/api/v1/log"; http_client_body; content:"gentlemen"; sid:1000001; rev:1;)
Abnormal DNS Queries (GIS/Infrastructure Servers)
alert dns $HOME_NET any -> any any (msg:"ET POLICY DNS Query for Known Gentlemen Ransomware Leak Site"; dns_query; content:".7mtzhh"; nocase; sid:1000002; rev:1;)
Encrypted File Exfiltration (Outbound)
alert tcp $HOME_NET any -> $EXTERNAL_NET any (msg:"ET POLICY Potential Large Data Exfiltration (Possible Ransomware Precursor)"; flow:established,to_server; threshold:type both, track by_src, count 50, seconds 60; sid:1000003; rev:1;)
SentinelOne
Malicious BitLocker Encryption (ANAR Tactic)
ProcessName RLIKE "manage-bde\.exe" AND Arguments RLIKE ".*-on.*-pw.*"
Context: Detects the command-line usage of BitLocker to encrypt drives with a password.
Gentlemen Ransomware Note Creation
EventType = "File Creation" AND FileName = "README-GENTLEMEN.txt"
Ransomware Extension Monitoring:
EventType = "File Rename" AND FileExtension = ".7mtzhh"
VSS Admin Backup Deletion
ProcessName = "vssadmin.exe" AND Arguments RLIKE ".*delete.*shadows.*"
Splunk
Detecting BitLocker Abuse (Event Code 4688):
index=windows sourcetype="XmlWinEventLog:Microsoft-Windows-Security-Auditing" EventCode=4688
NewProcessName="*\\manage-bde.exe"
| search CommandLine="*-on*" AND (CommandLine="*-password*" OR CommandLine="*-pw*")
| table _time, Computer, User, CommandLine
Gentlemen Ransomware File Activity:
index=main sourcetype="sysmon" EventCode=11
TargetFilename="*README-GENTLEMEN.txt"
| stats count by Computer, TargetFilename
ERP/Critical Application Access Spikes (Oltenia Tactic):
index=app_logs (sourcetype="erp_access" OR sourcetype="document_management")
| bucket _time span=1h
| stats count as access_count by _time, user, src_ip
| eventstats avg(access_count) as avg_count, stdev(access_count) as stdev_count
| where access_count > (avg_count + 3 * stdev_count)
Delivery Method
· Likely phishing or exploitation of a perimeter vulnerability.
Phishing email characteristics
Impersonation
· Emails often impersonate legitimate companies (e.g., gas or electric suppliers).
Lures
Recent 2025 campaigns utilized social engineering lures such as:
Urgent Promotions
· "There are 30 minutes left in our Holiday Crypto Promotion".
Financial Scams
· Promises of 10x returns on Bitcoin transfers.
Brand Hijacking
· Emails appearing from legitimate subdomains (e.g., b.grubhub.com) to bypass authentication checks.
References
Industrial Cyber
· hxxps://industrialcyber.co/critical-infrastructure/romanian-water-authority-energy-producer-hit-by-cyber-attacks-in-apparent-coordinated-holiday-campaign/
Research Checkpoint
· hxxps://research.checkpoint.com/2026/5th-january-threat-intelligence-report/
MalwareBazaar
· hxxps://bazaar.abuse.ch/sample/f8b07ce20ae77fec0905724a466196a5ba8281e9ba9534808ab7e7bf15f37516/
· hxxps://bazaar.abuse.ch/sample/51b9f246d6da85631131fcd1fabf0a67937d4bdde33625a44f7ee6a3a7baebd2/
