FORTRESS Explained #5

FORTRESS Explained #5:

What is ML-DSA, and why is it the new standard for digital signatures?

ML-DSA, the Module-Lattice-Based Digital Signature Algorithm, is stepping up to become the new global standard for digital signatures. Standardized by NIST as FIPS 204 in August 2024, it is a mathematical tool used to create digital signatures, which prove that a file, message, or software update is completely authentic and hasn’t been tampered with.

Where ML-DSA is used?

In short, ML-DSA is used wherever you need absolute proof that data is authentic. Its main real-life jobs are protecting smart car and phone updates so hackers can’t install viruses, verifying online banking websites so you know you aren’t on a fake phishing page, and locking down electronic legal contracts so they can’t be secretly altered.

Its advantage compared to other signature schemes such as RSA (Rivest-Shamir-Adleman) or ECC (Elliptic Curve Cryptography) is that it is believed to be resistant against attacks from quantum computers.

The physical attack surface

But as we discussed in our previous posts, a cryptographic algorithm is only as strong as its physical implementation. The math behind ML-DSA might be secure against a massive quantum computer, but what happens when an attacker gets their hands on the actual physical device performing that math?

Think back to the real-life applications above. If a hacker successfully uses a power-analysis attack to steal the private keys from a device’s Root of Trust, the consequences are severe. They could forge digital signatures, allowing them to bypass secure boot processes, impersonate trusted servers, or trick a device into installing malicious, unauthorized software updates.

The FORTRESS project evaluates the physical security of the Root of Trust systematically, considering multiple physical attack threats such as side-channel analysis or fault-injection attacks.