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ScanOnenote

Extracts embedded files in OneNote files.

Source code in strelka/src/python/strelka/scanners/scan_onenote.py
class ScanOnenote(strelka.Scanner):
    """Extracts embedded files in OneNote files."""

    def scan(self, data, file, options, expire_at):
        self.event["total"] = {"files": 0, "extracted": 0}

        try:
            # Searching for the magic string in the data
            for match in re.finditer(ONE_NOTE_MAGIC, data):
                self.event["total"]["files"] += 1

                try:
                    # Parsing the found object
                    obj = FileDataStoreObject.parse(data[match.span(0)[0] :])

                    # Sending extracted file back to Strelka for further analysis
                    self.emit_file(obj.FileData)
                    self.event["total"]["extracted"] += 1
                except Exception as e:
                    self.flags.append(
                        f"{self.__class__.__name__} Exception: {str(e)[:50]}"
                    )
        except Exception as e:
            self.flags.append(f"{self.__class__.__name__} Exception: {str(e)[:50]}")

Features

The features of this scanner are detailed below. These features represent the capabilities and the type of analysis the scanner can perform. This may include support for Indicators of Compromise (IOC), the ability to emit files for further analysis, and the presence of extended documentation for complex analysis techniques.

Feature
Support
IOC Support
Emit Files
Extended Docs
Malware Scanner
Image Thumbnails

Tastes

Strelka's file distribution system assigns scanners to files based on 'flavors' and 'tastes'. Flavors describe the type of file, typically determined by MIME types from libmagic, matches from YARA rules, or characteristics of parent files. Tastes are the criteria used within Strelka to determine which scanners are applied to which files, with positive and negative tastes defining files to be included or excluded respectively.

Source Filetype
Include / Exclude
application/msonenote
application/onenote
onenote_file

Scanner Fields

This section provides a list of fields that are extracted from the files processed by this scanner. These fields include the data elements that the scanner extracts from each file, representing the analytical results produced by the scanner. If the test file is missing or cannot be parsed, this section will not contain any data.

Field Name
Field Type
elapsed
str
flags
list
total
dict
total.extracted
int
total.files
int

Sample Event

Below is a sample event generated by this scanner, demonstrating the kind of output that can be expected when it processes a file. This sample is derived from a mock scan event configured in the scanner's test file. If no test file is available, this section will not display a sample event.

    test_scan_event = {
        "elapsed": 0.001,
        "total": {"extracted": 2, "files": 2},
        "flags": [],
    }