Capemon Skills

capemon is a sophisticated monitoring and instrumentation engine designed for malware analysis, configuration extraction, and payload recovery. It acts as the core injection component for the CAPEv2 sandbox.

Core Capabilities

1. API Hooking & Monitoring

capemon implements an extensive hooking engine derived from cuckoomon-modified, providing deep visibility into application behavior across multiple subsystems: - Process & Thread Management: Monitoring creation, termination, and manipulation of processes and threads. - File System Operations: Tracking file creation, deletion, reading, and writing. - Registry Activity: Capturing configuration changes and persistence mechanisms. - Network Communication: Intercepting socket operations, DNS queries, and high-level protocol activity (HTTP, etc.). - Cryptography: Extracting keys and monitoring encryption/decryption routines. - Synchronization & Services: Monitoring mutexes, events, and Windows Service interactions. - Windows Management Instrumentation (WMI): Intercepting WMI queries used for anti-analysis or reconnaissance. - Scripting Engines: Specific hooks for VBScript and other language runtimes.

2. Debugging & Tracing

capemon implements a powerful in-process debugger independent of Windows debugging interfaces, but harnessing the capabilities of the processor: - Hardware breakpoints: Four breakpoints bp0-bp3 that can be set on execute, read or write - Software breakpoints: Unlimited INT3 or 'CC' breakpoints overwriting instruction byte - Single-step: Tracing allows instruction-level capture enhanced with configurable step-over, trace-length, register changes, function names, strings & more - Actions: Configurable actions allow control flow manipulation with skipped or taken jumps, arbitrary register changes or jumps, string capture, dumps, scans & more - Programmable: Debugger configurable either on submission with simple text options or via dynamic YARA signature scans during unpacking or detonation - Integration: Hooking engine integrated with optional behavior log output & breakpoints set on return from hooked APIs (break-on-return) - Stealth: Debugger does not rely upon Windows interface and thus evades detection by a slew of interface-related indicators, with additional stealth from hook-based protections

3. Automated Unpacking

'capemon' implements a powerful unpacking engine using a combination of techniques - Memory region tracking: Regions of memory revealed through indicators of execution, allocation or protection are tracked - Early capture: Multiple possible triggers allow payload capture at earliest moment often resulting in working unpacked samples - Injection capture:: Strong coverage of injection techniques for inter-process payload capture - PE unmapping: Integrated Scylla engine allows capture of memory or file-mapped PE images in memory - Shellcode dumping: Shellcode * non-PE regions equally captured as payloads - Import Reconstruction: Repairing Import Address Tables (IAT) to create functional dumped executables. - AMSI Dumping: Intercepting and dumping buffers passed to the Antimalware Scan Interface (AMSI).

4. Config Extraction

Automated Static & Dynamic malware configuration extraction relies on 'capemon' capabilities - Static extraction: Typically reliant upon capemon's unpacking or process dump capture before static parsing - Dynamic extraction: When parser implementation is onerous, dynamic capture of decrypted configs can be performed by debugger via YARA signature

5. YARA integration

Integration of YARA for in-memory scanning - Dynamic configuration: Sandbox configuration such as hooking exclusions or options implemented during detonation - Debugger programming: Precise dydnamic breakpoint address resolution using YARA signatures & cape-specific metadata - Unpacking engine integration: Dynamic scanning of all memory regions prior to unpacking capture - Function resolution: Allows dynamic address resolution for APIs or functions for hooking or other purposes

Technical Foundations

• Platform: Windows (x86 and x64).
• Hooking Method: Inline hooking of Win32 and Native APIs (NTAPI).
• Debugger: Native in-process 'self' debugging utilising minimal OS interfaces & hardware capabilities (breakpoint, single-step)
• Dependencies:
  • distorm for instruction decoding.
  • libyara for pattern matching.
  • Scylla for PE reconstruction.
  • bson for data serialization.