Researchers crack homomorphic encryption

Thankfully nobody's using it yet

Homomorphic encryption is one idea offered to secure data in the cloud: the idea is to let software work on data without decrypting it.

It's mostly a research project at this stage, because it's very processor-intensive and therefore slow, and now one such scheme has the added problem of being vulnerable.

A trio of boffins from the Swiss Federal Institute of Technology in Lausanne has published their work at the IACR, here.

They took a look at a 2014 scheme proposed by MIT's Hongchao Zhou and Gregory Wornell.

The EPFL paper, by Sonia Bogos, John Gaspoz and Serge Vaudenay, demonstrates attacks against the scheme's broadcast encryption, a “chosen ciphertext attack”, and a plaintext attack.

Strike one: The scheme proposed encryption for broadcast messages, to support data sharing. However, the EPFL paper says an attacker that eavesdrops on broadcast traffic would get “enough information to solve the system”.

“A valid scenario for this attack would be one where a service provider has to send an activation key to its customers. The activation key is the same for all the customers. In such case, when the service provider has to send the encrypted activation key to enough customers, an unauthorised user could recover the activation key”, the authors write.

Strike two: In the chosen ciphertext attack, they write, an attacker with access to an oracle that decrypts the text can run a brute-force to recover the encryption key.

Strike three: As with the chosen ciphertext attack, the plaintext attack is a successful brute force against the encryption.

All of which means the EPFL boffins have sent the MIT homomorphic encryption scheme back for some warranty fixes. ®

Other stories you might like

  • Running Windows 10? Microsoft is preparing to fire up the update engines

    Winter Windows Is Coming

    It's coming. Microsoft is preparing to start shoveling the latest version of Windows 10 down the throats of refuseniks still clinging to older incarnations.

    The Windows Update team gave the heads-up through its Twitter orifice last week. Windows 10 2004 was already on its last gasp, have had support terminated in December. 20H2, on the other hand, should be good to go until May this year.

    Continue reading
  • Throw away your Ethernet cables* because MediaTek says Wi-Fi 7 will replace them

    *Don't do this

    MediaTek claims to have given the world's first live demo of Wi-Fi 7, and said that the upcoming wireless technology will be able to challenge wired Ethernet for high-bandwidth applications, once available.

    The fabless Taiwanese chip firm said it is currently showcasing two Wi-Fi 7 demos to key customers and industry collaborators, in order to demonstrate the technology's super-fast speeds and low latency transmission.

    Based on the IEEE 802.11be standard, the draft version of which was published last year, Wi-Fi 7 is expected to provide speeds several times faster than Wi-Fi 6 kit, offering connections of at least 30Gbps and possibly up to 40Gbps.

    Continue reading
  • Windows box won't boot? SystemRescue 9 may help

    An ISO image you can burn or drop onto a USB key

    The latest version of an old friend of the jobbing support bod has delivered a new kernel to help with fixing Microsoft's finest.

    It used to be called the System Rescue CD, but who uses CDs any more? Enter SystemRescue, an ISO image that you can burn, or just drop onto your Ventoy USB key, and which may help you to fix a borked Windows box. Or a borked Linux box, come to that.

    SystemRescue 9 includes Linux kernel 5.15 and a minimal Xfce 4.16 desktop (which isn't loaded by default). There is a modest selection of GUI tools: Firefox, VNC and RDP clients and servers, and various connectivity tools – SSH, FTP, IRC. There's also some security-related stuff such as Yubikey setup, KeePass, token management, and so on. The main course is a bunch of the usual Linux tools for partitioning, formatting, copying, and imaging disks. You can check SMART status, mount LVM volumes, rsync files, and other handy stuff.

    Continue reading

Biting the hand that feeds IT © 1998–2022