Other files contained text or code that, with the correct program or instructions, could be converted into images of a sensitive and possibly illegal nature. (Due to the very limited size restrictions per “block” on the blockchain, full images or large amounts of text must be parceled out into multiple entries.)
These examples are likely only the tip of the iceberg in terms of suspicious content already on the blockchain, the authors emphasize, as many methods for locating hidden files are currently indecipherable without insider knowledge. Plus, new arbitrary data is being continually added.
“Although court rulings do not yet exist, legislative texts from countries such as Germany, the UK, or the USA suggest that illegal content such as child pornography can make the blockchain illegal to possess for all users,” they write, adding that a total of 112 nations have laws against child pornography.
Previous investigations had already raised the alarm over upsetting content within the blockchain, but no nations instituted bans for these reasons. However, in light of their findings, the authors fear that Bitcoin and other blockchain-based cryptocurrencies could be jeopardized over the system’s built-in exploitability in the future.