When Data Mining Conti Leaks Leads to Actual Binaries and to a Hardcoded C2 With an Encryption Key on Tripod.com – Part Three
Dear blog readers,
Continuing the “When Data Mining Conti Leaks Leads to Actual Binaries and to a Hardcoded C2 With an Encryption Key on Tripod.
When Data Mining Conti Leaks Leads to Actual Binaries and to a Hardcoded C2 With an Encryption Key on Tripod.com – Part Three
Dear blog readers,
Continuing the “When Data Mining Conti Leaks Leads to Actual Binaries and to a Hardcoded C2 With an Encryption Key on Tripod.com – Part Two” blog post series in this post I’ll continue analyzing the next malicious software binary which I obtained by data mining Conti Leaks with a lot of success.
The actual malicious software binary location URL:
hxxp://shighil.com/dl2.exe
MD5: c2055b7fbaa041d9f68b9d5df9b45eddSHA-1: e4bd443bd4ce9029290dcd4bb47cb1a01f3b1b06SHA-256: 342f04c4720590c40d24078d46d9b19d8175565f0af460598171d58f5ffc48f3
Here’s the actual analysis.
Executive Summary
dl2.exe is a Windows x86_64 PE executable (849.5 KB) exhibiting characteristics consistent with malicious software. The binary demonstrates sophisticated capabilities including registry manipulation, dynamic API resolution, file system operations, and system information gathering. Analysis identified multiple high-risk behaviors typical of malware, particularly around persistence mechanisms and anti-analysis techniques.
Key Findings
Critical Capabilities (High Severity)
1. Registry Manipulation
Functions: sub_419118, sub_419228, sub_419198, sub_4192e8, sub_4193c4, sub_40da8c, sub_422ef4, sub_418ffc
APIs Used: RegOpenKeyA, RegSetValue, RegCreateKey, RegQueryValue
Registry Keys Accessed:
SoftwareMicrosoftWindowsCurrentVersion
RestrictRun and NoRun keys (policy restriction keys)
Risk: High – Can modify system configuration and establish persistence
2. Dynamic API Resolution
Function: sub_40b868 (0x40b868)
APIs Used: GetProcAddress, LoadLibrary, GetModuleHandle
Risk: High – Common evasion technique to bypass static analysis and API monitoring
Details: Dynamically resolves function addresses at runtime, making static detection more difficult
Medium Severity Capabilities
3. File System Operations
Functions: sub_423718, sub_4228a4, sub_423360, sub_41aeec
APIs Used: CreateFile, DeleteFile, MoveFile, CopyFile, FindFirstFile, FindNextFile, GetFileAttributes
Risk: Medium – Can manipulate files on the system
4. System Information Gathering
Functions: sub_4542b0, sub_40f0ac, sub_46df44, sub_46d3bc
APIs Used: GetVersionExA, GetSystemInfo, GetComputerName, GetUserName
Risk: Medium – Fingerprints the system, likely for profiling or anti-VM checks
5. Memory Manipulation
Functions: sub_4540e0, sub_453df0, sub_453d10, sub_453b50
APIs Used: VirtualAlloc, VirtualProtect, HeapAlloc, HeapFree
Risk: Medium – Can change memory protection flags, potentially indicating code injection or unpacking behavior
6. Mutex Creation
Function: sub_46be50 (0x46be50)
API Used: CreateMutex
Risk: Medium – Commonly used for single-instance enforcement in malware
Security Features (Informational)
7. Stack Protection Mechanisms
Stack Cookie Initialization (sub_45ca90 at 0x45ca90): Uses multiple entropy sources (GetSystemTimeAsFileTime, GetCurrentProcessId, GetCurrentThreadId, GetTickCount, QueryPerformanceCounter) to generate stack cookies
Stack Guard Pages (sub_4540e0 at 0x4540e0): Implements guard pages using VirtualQuery, VirtualAlloc, and VirtualProtect
Notable Observations
Entry Point: 0x4545a0 (_start)
Main Function: 0x46d9f4 (jumps to 0x46da1c)
Imported Libraries: ADVAPI32.dll, GDI32.dll, KERNEL32.dll, OLEAUT32.dll, SHELL32.dll, SHLWAPI.dll, USER32.dll, WINSPOOL.DRV, comdlg32.dll, ole32.dll, oledlg.dll
Total Functions Identified: 2,616
No Network APIs Detected: No direct socket, HTTP, or network communication APIs were found in the analyzed functions (analysis incomplete)
No Obvious Encryption Strings: No strings matching common encryption algorithm names were found
Malware Classification
Based on identified capabilities, this binary exhibits behaviors consistent with:
System modification malware (registry manipulation, file operations)
Information stealer (system information gathering)
Potentially a dropper/loader (dynamic API resolution, memory manipulation)
Critical Malicious Capabilities Identified
1. Windows Policy Restriction Manipulation (HIGH SEVERITY)
The binary targets multiple Windows policy registry keys designed to restrict user actions:
Registry Keys Targeted:
SoftwareMicrosoftWindowsCurrentVersionPoliciesExplorer
NoRun – Prevents running programs via Run dialog
RestrictRun – Restricts which programs can execute
NoDrives – Hides/restricts drive access
NoNetConnectDisconnect – Prevents network connections/disconnections
NoRecentDocsHistory – Disables recent documents
NoClose – Prevents closing windows
SoftwareMicrosoftWindowsCurrentVersionPoliciesNetwork
NoEntireNetwork – Restricts network browsing
SoftwareMicrosoftWindowsCurrentVersionPoliciesComdlg32
Common dialog restrictions
Functions Involved:
2. Console Output Manipulation
sub_46be50 (0x46be50) – Opens CONOUT$ device handle, likely for output redirection or hiding console output
3. Persistence & Configuration
The binary uses both registry and INI file storage for configuration, with registry taking precedence. This dual-storage approach suggests:
Fallback mechanisms for different environments
Ability to persist settings across system changes
Summary of Malicious Findings
This binary is highly malicious with the following critical behaviors:
Primary Threat: System Restriction Malware
The binary manipulates Windows Group Policy registry keys to:
Disable the Run dialog (NoRun)
Restrict program execution (RestrictRun)
Hide/disable drives (NoDrives)
Prevent network operations (NoNetConnectDisconnect, NoEntireNetwork)
Disable system features (NoClose, NoRecentDocsHistory)
This behavior is characteristic of ransomware preparation, system lockers, or destructive malware that prevents users from:
Running recovery tools
Accessing safe mode
Using system utilities
Connecting to networks for help
Additional Malicious Capabilities:
Dynamic API resolution – Evades static analysis
Dual persistence – Registry + INI file storage
Console manipulation – Hides output/errors
File system operations – Can modify/delete files
Memory manipulation – Can inject code or unpack payloads
System fingerprinting – Profiles victim environment
*** This is a Security Bloggers Network syndicated blog from Dancho Danchev’s Blog – Mind Streams of Information Security Knowledge authored by Dancho Danchev. Read the original post at: https://ddanchev.blogspot.com/2026/03/when-data-mining-conti-leaks-leads-to_029886864.html
