# Summary The submitted sample is a 32-bit Windows Portable Executable (#AID=23#) of approximately 1017 KB. The file is heavily obfuscated, likely packed by a custom or private packer. It features a legitimate-looking but suspicious digital certificate issued to "Umbrella LLC" in Krasnoyarsk, Russia, and contains a massive import table heavily comprised of unreferenced APIs (decoy imports). The entry point executes a standard unpacking stub: allocating memory via `VirtualAlloc`, performing XOR-based decryption/copying, and jumping to the newly allocated region to execute the hidden payload. No clear legitimate application behavior or GUI strings are visible in the unpacked state. # Key detections/IOCs - **Hash**: `0dc710737c12ea1c1215fbd39e00347649fff1fb0e512287c86873f66a9f0a35` - **Certificate Subject**: Umbrella LLC (Locality: Krasnoyarsk, Country: RU) - **Certificate Email**: umbrella.smolyaninov@yandex.ru - **Certificate Issuer**: Sectigo RSA Code Signing CA - **Unreferenced Imports**: Over 200 imported Windows API functions (from `advapi32`, `kernel32`, `user32`, etc.) have zero cross-references in the code, a classic anti-static-analysis technique. - **Packing/Unpacking Indicators**: The entry point (`EntryPoint` at 0x2C8A) calls a decryption routine and jumps to a dynamically allocated memory region (`VirtualAlloc`). High frequency of XOR operations (`XorInLoop` anomalies) and sequential execution flow. # Evidence - **Obfuscation**: The code at the entry point and its callees (`sub_408352`, `sub_40455f`) manually resolve APIs using `LoadLibraryA`, `GetModuleHandleA`, and `GetProcAddress`, bypassing the static Import Address Table (IAT). The .text section entropy (5.4) combined with 201 unreferenced imports indicates the binary is packed or heavily VM-protected. - **Virtual Files**: A single virtual resource (#AID=24#) located at `MANIF/1/hu-hu` was extracted. Decompiling it reveals a standard Windows Application Manifest requesting `asInvoker` privileges, which provides no additional behavioral insight beyond standard execution. - **Certification**: The code signature contains valid certificate chains pointing to Sectigo, but the subject details (Umbrella LLC, Krasnoyarsk, RU) combined with a yandex.ru email address are highly suspicious and typical of crimeware or stolen certificates used to bypass Windows Defender SmartScreen. - **Resource Section**: The resource section (`.rsrc`) contains padding data (`PADDINGXXPADDING...`) and an anomaly of extra space after the resources directory, likely used to pad the file size or hide embedded payloads. # Verdict **Malicious (High Confidence)** **Score: 75/100** While the binary does not exhibit overt network calls or destructive filesystem operations in its exposed strings and entry point, the structural evidence is overwhelming: a custom unpacking stub, API resolution via dynamic hashing/loading, hundreds of decoy imports, and a suspicious Russian code-signing certificate. This profile perfectly matches a packed dropper, Trojan, or infostealer prepared for malicious deployment. The actual malicious payload resides in the decrypted memory region executed at runtime.