Someone added images of child sexual abuse to an immutable blockchain ledger, the BBC reported. The images were added to the Bitcoin Satoshi Vision (BSV) core ledger through the payment processing app Money Button.
When someone completes a transaction on the BSV blockchain, it is encoded into a block of data, which is signed by the buyer, and then added to a set chain of prior cryptocurrency transactions. In this instance, the individual used the payment app to effectively upload the image to the blockchain.
Last month, a Bitcoin SV developer announced that he and other miners had increased data limits on transactions to 100KB (in what he characterised as the “unfuckening”), meaning that individuals can now store webpages, images, and video in just one transaction.
The person who shared child sexual abuse on BSV reportedly did so by uploading the image to their Money Button transaction, which was then added to the digital block of data on the immutable ledger. Money Button confirmed that this was the case in a blog post on Friday, stating that its service doesn’t have a way to “interpret or display” the content it processes, but BitcoinFiles.org does, and was notified by local authorities that there was illegal content on its site.
Money Button wrote that “BitcoinFiles.org removed the content from their website and then contacted us suspecting that Money Button may have been the tool the criminals used to write this content to the blockchain”
“We have confirmed that was the case and we have banned the user responsible for creating those transactions,” Money Button wrote. “We believe it is important to be proactive about moderating content. Now that Bitcoin SV has the ability to write large amounts of data to the blockchain, it is likely that criminals will continue to attempt to abuse this technology for illegal purposes.”
The payment processor added that it updated its terms of service “to explicitly clarify that Money Button cannot be used to write illegal content to the blockchain, and users who attempt to do so will be banned and reported to the authorities.”
This isn’t the first time child abuse images were shared on the blockchain—in March of last year, researchers in Germany found that of 1,600 files stored on Bitcoin’s blockchain, two included lists of links to child porn, according to the paper.
The lists included a total of 274 links to websites, with more than half of those linking to Tor hidden services. Another file included “an image depicting mild nudity of a young woman.” The researchers noted that an online forum claims that it is child porn, but that this couldn’t be verified.
“The Bitcoin SV block chain is not a place for criminal activity,” Jimmy Nguyen, founder of nChain, the company that runs BSV, told BBC, “and if you use it for illegal purposes, you will leave a digitally signed evidence trail that cannot be erased.”
This capability raises concerns over the immutable nature of the blockchain—that illegal content, including child abuse imagery, can be permanently added to a ledger. It also points to a future in which blockchain hosts need to roll out stronger moderation efforts, such as blacklists, ensuring illegal content isn’t shared and viewed.