Undoubtedly, the capability to create a copy of a web page and save it locally is especially important for Digital Investigators. For example, there may be situations where a social media page or a site suspected to be involved in the sale of illicit material needs to be locally saved for reference. There is an abundance of tools that can achieve this task, but for this OSINT Tool Review article, we will present ‘SingleFile’, a very popular web extension and command-line interface tool that is compatible with Chrome, Firefox (Desktop and Mobile), Microsoft Edge, Vivaldi, Brave, Waterfox, Yandex Browser, and Opera.

For the benefit of our readers, the links to the tools can be accessed below:

• Firefox: https://addons.mozilla.org/firefox/addon/single-file
• Chrome: https://chrome.google.com/extensions/detail/mpiodijhokgodhhofbcjdecpffjipkle
• Microsoft Edge: https://microsoftedge.microsoft.com/addons/detail/efnbkdcfmcmnhlkaijjjmhjjgladedno

So, how does it work? During our tests, we found that installing and deploying the extension is incredibly straightforward. Once the extension is installed onto your browser of choice, you can open a target web page and then click on the ‘SingleFile’ extension icon located at the top-right hand side of your browser. At this point, the extension does all of the hard work and creates a copy of the target page and saves it locally on your system as an HTML file. The extension itself is highly flexible and users can configure the tool depending on their overall needs by right-clicking the extension’s icon and selecting the ‘options’. For example, users can configure the user interface, specify file names, configure what HTML content should be extracted and remove scripts (to name but a few!).

In addition to the capabilities indicated above, ‘SingleFile’ allows Digital Investigators to batch save all tabs within their browser window and annotate saved web pages with the use of a neat editor. But, what we consider to be the most valuable capability, is that it allows Digital Investigators to turn on the auto-save function which will save each web page that is opened within the browser. Lastly, the tool is very flexible with regards to integrations with user scripts – this enables Digital Investigators to implement user scripts such as auto-click and auto-scroll.

It goes without saying, this tool is impressive. However, the developers have recognised some teething problems with regards to using the extension when incognito mode. Also, while the command-line interface version of the tool can be used to save Onion web pages; the extension, on the other hand, is not compatible with Tor.

One very important point we wish to make at this stage is that tool only allows Digital Investigators to save web pages as HTML, there remains no capability to save as PDF. Also, we must also point out that the tool does not forensically save web pages – this is important for investigators that require a forensically secure copy that can be presented as evidence before a court. For example, HTML copies of web pages can easily be edited locally through the use of a text editor, whereas editing a PDF is less easy. In the same regard, digital evidence should also be hashed at source, thus certifying that it is a forensically secure copy. Therefore, while ‘SingleFile’ is a useful tool for creating a copy of a web page – perhaps for research purposes – we strongly advise that Digital Investigators look at specialised forensic browsers that have the capability to create secure copies of web pages and hash them immediately upon extraction. The titan of forensic browsers is undoubtedly Paliscope Discovry as it has the capability to create forensic copies of web pages in HTML and PDF. Additionally, Paliscope Discovry can be used to create forensic copies of Onion web pages.