Privacy is not dead yet

While some politicians keep pushing for “lawful access” to our private messages, a new method may make it possible to keep our private communications private – even if end-to-end encryption in, for instance, Signal is “lawfully” decrypted. Associate professor at the IT University of Copenhagen, Rosario Giustolisi, explains how.

Written 14 December, 2025 17:12 by Jari Kickbusch

Critics of Chat Control warned that the European Union proposal to scan messages for child sexual abuse material would pave the way for mass surveillance, essentially causing the death of privacy. The proposal was blocked by German politicians, but should the political wish to access our messages surface again, there is hope for those who would like their private communications to stay private. As part of an international research group, associate professor at the IT University of Copenhagen, Rosario Giustolisi, is investigating whether it's possible for Signal users to preserve private communications while an adversary decrypts the end-to-end encryption, on which privacy depends. In short, the surprising answer is "yes".

"We have indications that even if all decryption keys are exposed, covert channels that preserve normal protocol behaviour can still exist," says Rosario Giustolisi.

End-to-end encryption

End-to-end encryption is a security method that ensures only the communicating parties can read the messages being exchanged. When communicating, the data is encrypted on the sender’s device before it leaves, and only the intended recipient’s device can decrypt the data. Service providers, network operators, or whoever it might be cannot read the content because they do not have the decryption keys. This is why end-to-end encryption has been the gold standard for private messaging for a long time, and is used by apps like Signal, WhatsApp, Facebook Messenger, and Google Messages.

"If the politicians at some point should require companies like Signal and Meta to provide a way for the authorities to decrypt messages, it will be the end of end-to-end encryption. There will be a need to develop new solutions for people who think that privacy is important," says Rosario Giustolisi.

Anamorphic encryption

The method used to communicate in private when end-to-end encryption applications are compromised is called anamorphic encryption. Anamorphic encryption is a distorted projection or drawing that appears normal when viewed from a particular point. Photographers, for example, work with anamorphic processes or lenses that distort an image by squashing or squeezing it horizontally. Similarly, Rosario Giustolisi and his fellow researchers use the method to hide private messages inside normal-looking encrypted traffic.

"Basically, you hide your messages inside something that looks innocent. This can only be done by the user. So Signal or Meta don't have to do anything; in fact, they cannot prevent it from happening unless they change their encryption systems," says Rosario Giustolisi.

A hope for privacy?

Rosario Giustolisi sees anamorphic encryption as a potential opportunity for people who insist on the right to communicate without any company or state looking over their shoulder. However, he does mot think that it will be the only solution if politicians should get “lawful access” to our private messages in Signal, Facebook Messenger, and similar services 

"People will find new ways. There will always be new ways to communicate in private, and especially people who have something to hide, will find those ways," he ends.