Standard encryption is widely used across the internet for all kinds of services, including banking apps, health records and messaging services. It is used to keep private information private. End-to-end encryption (E2EE) goes a step further, meaning only the sender and intended recipient hold the keys needed to ‘unlock’ or decrypt the message.
Over recent years, an increasing number of digital platforms have implemented E2EE and are no longer deploying proactive detection. This makes it harder to detect criminal content, like CSAM (child sexual abuse material), by securely scanning imagery against lists of known illegal content.
IWF’s explainer delves into how platforms can prevent the upload of CSAM in E2EE environments in a privacy preserving way. Upload prevention is a method that works and is already being used by companies to check for other types of content. It is time these safety checks also extended to CSAM. Governments must require companies to implement the upload prevention method on their E2EE services and reduce the risk of known CSAM being sent and shared on their services. Implementing upload prevention will be a crucial step in preventing offenders from sharing known CSAM on E2EE messaging.
Services that adopt end-to-end encryption must also adopt upload prevention, ensuring that known CSAM is detected and blocked before it can be shared. In doing so, platforms can uphold both the security of private communications and the fundamental rights of victims and survivors.
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