- doc
- sensitive documents
- Metadaten aus Dateien entfernen
Was sind Metadaten?
Metadaten sind "Daten über Daten" oder "Informationen über Informationen", die (in der Regel automatisch) in Computerdateien eingebettet sind. Metadaten werden verwendet, um Dateien zu beschreiben, zu identifizieren, zu kategorisieren und zu sortieren.
Metadaten können jedoch auch dazu verwendet werden, Nutzer zu deanonymisieren und private Informationen preiszugeben.
Beispiele für Metadaten sind:
In image files:
The location where a photo was taken
The date and time a photo was taken
The model and serial number of the camera used to take a photo
In text document files:
The author of the document
Changes to the document
To learn more about how metadata can be used to identify and reveal personal information, see Behind the Data: Investigating metadata.
It is impossible to reliably find and remove all metadata in complex file formats. For example, Microsoft Office documents can contain embedded images, audio, and other files containing their own metadata that Tails cannot remove.
Sie sollten Metadaten von Dateien entfernen, bevor Sie sie in ein anderes Dokument einbetten.
Also, you should save files in simpler formats whenever possible. For example, instead of saving a text document as a .docx file, you can save the document as a plain .txt file.
Removing metadata using Metadata Cleaner
Tails includes Metadata Cleaner so you can remove metadata from files before you publish or share them.
Metadata Cleaner works on many file formats, including:
Image files, such as .jpeg, .png, and .gif
LibreOffice files, such as .odt and .ods
Microsoft Office documents, such as .docx, .xlsx, and .pptx
Audio files, such as .mp3, .flac, and .ogg
Video files, such as .mp4 and .avi
Archive files, such as .zip and .tar
To open Metadata Cleaner choose Applications ▸ Accessories ▸ Metadata Cleaner.
Removing metadata from the command line
Metadata Cleaner is a graphical interface for mat2.
You can also use mat2 directly on the command line:
Open a Terminal.
Execute the following command.
Replace file.ext with a path to the file that you want to clean.
mat2 file.ext
After mat2 finishes, a copy of your file without metadata is available as file.cleaned.ext.