I previously wrote that Apple scans uploaded iCloud content for child abuse imagery. Apple’s privacy officer confirmed this. Now a search warrant reveals that the company is also scanning emails (via Forbes).
Hashes
Apple uses an automated system to scan emails. One such popular system is PhotoDNA, although it’s unknown if Apple uses that service. It creates a hash out of images and compares the hash to a database filled with hashes of known child pornography. When the system detects a hash, it gets flagged for manual review.
In the search warrant, an officer in an investigation mentioned an Apple employee’s comments about one such detection.
When we intercept the email with suspected images they do not go to the intended recipient. This individual … sent 8 emails that we intercepted. [Seven] of those emails contained 12 images. All 7 emails and images were the same, as was the recipient email address. The other email contained 4 images which were different than the 12 previously mentioned. The intended recipient was the same,” the Apple workers’ comments read.
“I suspect what happened was he was sending these images to himself and when they didn’t deliver he sent them again repeatedly. Either that or he got word from the recipient that they did not get delivered.
Apple is able to do this email scanning because emails are typically only encrypted in transit, not on the servers.
Further Reading
[Apple Now Scans Uploaded Content for Child Abuse Imagery]
[CES 2020: Apple Privacy Chief Defends Company Stance on Encryption and Backdoors]