QuickSand Version 2.3

QuickSand Python Package and Command-Line Tool

QuickSand is a fast, self-contained Python analysis framework for analyzing suspected malware documents and PDFs to identify exploits, obfuscated scripts, embedded executables, and high-risk active content across nested streams, encodings, and compressions.

QuickSand uses native Python standard-library binary parsers inside a single module (src/quicksand/quicksand.py) paired with YARA signatures (yara-python>=4.3.0 is the only external dependency).

A hosted version is available to try without any installation at scan.tylabs.com.

Supported Formats & Capabilities

• OLE2 Compound Files ([MS-CFB]): Native parsing of .doc, .xls, .ppt, .msg, and HWP documents, including FAT/DIFAT/MiniFAT stream extraction, [MS-OLEPS] SummaryInformation / DocumentSummaryInformation metadata extraction, and [MS-OXRTFCP] Outlook MAPI Compressed RTF (LZFu / MELA) decompression.
• VBA Macros ([MS-OVBA]): Native decompression of compressed VBA macro streams (Macros, _VBA_PROJECT_CUR, VBA) while also scanning raw streams to catch VBA stomping / p-code tampering.
• Excel 4.0 (XLM) Macros ([MS-XLS]): Native BIFF5/BIFF8 scanner for BOUNDSHEET macro sheets, Auto_Open / Auto_Close built-in labels, FORMULA tokens (EXEC, CALL, REGISTER, CHAR, GET.WORKSPACE), SST, and DCONN data connections.
• Encrypted Office Documents ([MS-OFFCRYPTO]): Built-in detection and in-memory decryption of ECMA-376 Standard Encryption (AES-128/192/256 & CryptoAPI RC4) and Agile Encryption (XML v4.4) using user-supplied passwords and common malware passwords (such as VelvetSweatshop).
• Rich Text Format (RTF): Native extraction of \objdata, ods, and datastore hex streams, OLE 1.0 objects (e.g., Equation Editor Equation.3), trailing \objdata presentation streams (CVE-2025-21298), and OLEPackage embedded files (with resilience against RTF control-word obfuscation).
• PDF Documents: Native stream parser and filter pipeline supporting /FlateDecode (including PNG row predictors 10–15), /ASCIIHexDecode, /ASCII85Decode, /LZWDecode, /RunLengthDecode, #xx hex-escaped dictionary/filter names, /EmbeddedFile recursive scanning, Widget /V Base64 payload decoding (CVE-2026-34621), and PDF 1.5+ /ObjStm compressed object streams.
• OpenXML / ZIP / Archive Containers: Extraction and recursive analysis of .docx, .xlsx, .pptx, embedded archives, ZIP entry filename manifests (CVE-2023-38831, CVE-2025-59689), WinRAR ADS path traversal (CVE-2025-8088), relationships (oleObject, aFChunk, external templates), and ActiveX controls.
• MIME / MHT / ActiveMime / WordML (mso): Base64 decoding and zlib inflation of ActiveMime headers and embedded payloads.
• PostScript (ps), OneNote (.one), Flash (CWS/FWS), & Windows Shell (.lnk, .library-ms, .settingcontent-ms): Hex/zlib payload extraction and embedded script, deserialization, NTLM coercion, and executable detection.

Parser Hardening & Security

Because all format parsers in src/quicksand/quicksand.py are written in memory-safe pure Python with explicit bounds checks, document buffer-overflow exploits (such as Equation Editor stack overflows or RTF \fonttbl heap corruption) cannot corrupt memory in QuickSand. In addition, QuickSand enforces strict resource limits against parser Denial-of-Service (DoS) attacks:

• Decompression & Zip Bomb Protection: All zlib, PDF /FlateDecode, /LZWDecode, /RunLengthDecode, MS-OVBA, and OpenXML ZIP stream reads are capped at 32 MB (MAX_DECOMPRESSED_STREAM_SIZE) with archive entry limits (MAX_ARCHIVE_ENTRIES = 1024).
• Cycle & Depth Guards: OLE FAT/DIFAT/MiniFAT chains track visited sectors to prevent infinite loops, directory tree walks are depth-bounded, and recursive container analysis is capped at MAX_NESTING_DEPTH = 10.
• Header & Crypto Bounds: PDF PNG predictor column widths (<= 65536), OLE sector shifts (512 or 4096 bytes), and Agile Encryption KDF spinCount (<= 250,000) are validated, and <!DOCTYPE / <!ENTITY declarations are rejected to prevent XML Billion Laughs attacks.

Repository Structure

• src/quicksand/quicksand.py: Single-file QuickSand engine, native format parsers, and CLI entry point.
• src/quicksand/quicksand_exploits.yara: YARA signatures for Office, RTF, VBA, XLM, OpenXML, and OneNote exploits and warnings.
• src/quicksand/quicksand_pdf.yara: YARA signatures for PDF exploits, JavaScript obfuscation, and active content.
• src/quicksand/quicksand_exe.yara: YARA signatures for embedded PE/ELF binaries, LNK shortcuts, HTA/SCT scriptlets, and encoded payloads.
• bin/quicksand: Command-line wrapper script.
• quicksand.spec: PyInstaller specification for building standalone single-file executables (quicksand.exe, quicksand-linux-x86_64, quicksand-macos-arm64).
• .github/workflows/build-windows-exe.yml: GitHub Actions workflow for building standalone executables across Windows, Linux, and macOS.
• .github/workflows/publish-pypi.yml: GitHub Actions workflow for building and publishing the Python package to PyPI.
• gcloud/: Optional Google Cloud Run functions.
• lambda/: Optional AWS Lambda functions.

Dependencies

• Python >= 3.7
• yara-python >= 4.3.0

Installation

Install from PyPI

pip3 install quicksand

Upgrade from PyPI

pip3 install --upgrade quicksand

Install from Source

git clone https://github.com/tylabs/quicksand.git
cd quicksand
pip3 install .

Building a Standalone Windows Executable (quicksand.exe)

When installed via pip install . on Windows, pip automatically creates a quicksand.exe CLI wrapper in your Python Scripts\ directory.

To build a portable, single-file dist\quicksand.exe (which includes Python, yara-python, and all .yara rule files so no Python installation is required on the target machine):

pip install -r requirements.txt pyinstaller
pyinstaller --clean quicksand.spec

Tip: The standalone quicksand.exe uses its bundled .yara rules automatically, or you can place custom quicksand_exploits.yara, quicksand_exe.yara, or quicksand_pdf.yara files in the same folder as quicksand.exe to override them without rebuilding.

Command-Line Usage

usage: quicksand [-h] [--version] [-v] [-c] [-y] [-t SECONDS] [-p PASSWORD]
                 [-d DIR] [-f {json,txt}] [-o FILE] [-e FILE] [-x FILE]
                 [-a FILE]
                 document

QuickSand v2.3.0 - Document and PDF malware analysis tool.
Scans nested streams inside Office (OLE2, OpenXML, RTF, VBA, XLM), PDF,
MIME/ActiveMime, PostScript, and OneNote files using YARA signatures.

positional arguments:
  document              path to a document file or directory of documents to
                        scan

options:
  -h, --help            show this help message and exit
  --version             show program's version number and exit

analysis & extraction options:
  -v, --verbose         enable verbose diagnostic logging during analysis
  -c, --capture         capture decoded stream contents in results
  -y, --yara            include matched YARA string offsets and previews in
                        output
  -t SECONDS, --timeout SECONDS
                        per-file analysis timeout in seconds (default: 0 =
                        unlimited)
  -p PASSWORD, --password PASSWORD
                        password for decrypting protected Office documents
  -d DIR, --dropdir DIR
                        directory to write extracted binary streams to
                        (implies --capture)

output options:
  -f {json,txt}, --format {json,txt}
                        report output format: 'json' or 'txt' (default: json)
  -o FILE, --out FILE   write report output to FILE instead of stdout

custom YARA signature options:
  -e FILE, --exploit FILE
                        custom path to exploit YARA rules (default: bundled
                        quicksand_exploits.yara)
  -x FILE, --exe FILE   custom path to executable YARA rules (default: bundled
                        quicksand_exe.yara)
  -a FILE, --pdf FILE   custom path to PDF YARA rules (default: bundled
                        quicksand_pdf.yara)

examples:
  quicksand suspicious.doc
  quicksand -f txt -y invoice.pdf
  quicksand -p VelvetSweatshop encrypted.xls
  quicksand -d extracted_streams/ -o report.json samples_dir/

Scan a Single Document

quicksand document.doc

Scan a Directory of Documents and Save Text Report

quicksand -f txt -o report.txt malware_samples/

Extract Decoded Streams to Disk

quicksand -d extracted_streams/ suspicious.rtf

Python Module Usage

Scan a Document from Memory (bytes)

import pprint
from quicksand import quicksand

with open("document.doc", "rb") as f:
    data = f.read()

qs = quicksand(data, timeout=18, strings=True)
qs.process()
pprint.pprint(qs.results)

Scan a Document by File Path

from quicksand import quicksand

qs = quicksand("file.pdf")
qs.process()
print(qs.results["risk"], qs.results["score"], qs.results["rating"])

Scan All Files in a Directory

from quicksand import quicksand

results = quicksand.readDir("malware_samples/")

Returns a dictionary mapping {filepath: qs.results, ...}.

Optional quicksand(...) Parameters

• capture (bool, default False): Store decoded stream bytes in results["streams"].
• strings (bool, default True): Include matched YARA string offsets and previews in results["results"].
• debug (bool, default False): Print debug trace messages during parsing.
• timeout (int, default 0): Maximum processing time in seconds (0 for unlimited).
• password (str, default None): Password to try when decrypting password-protected Office documents (tried before the built-in default password list).
• exploityara, execyara, pdfyara (str, default None): Custom paths to override the bundled YARA rule files.

Scoring & Risk Ratings

Each YARA signature defines metadata classifying the detection (is_exploit, is_warning, is_feature, is_exe), a rank score weight, and MITRE ATT&CK® technique IDs (mitre).

To prevent double-counting when the same content appears in both a raw stream and a decompressed child stream, QuickSand deduplicates each rule's score contribution per document while recording all matching stream locations in results["results"].

For more details on interpreting results, see scan.tylabs.com/howto.

Using QuickSand?

Let us know @tylabs

Issues and Project Home

QuickSand GitHub