| ID |
CVE-2024-1544
|
| Sažetak |
Generating the ECDSA nonce k samples a random number r and then
truncates this randomness with a modular reduction mod n where n is the
order of the elliptic curve. Meaning k = r mod n. The division used
during the reduction estimates a factor q_e by dividing the upper two
digits (a digit having e.g. a size of 8 byte) of r by the upper digit of
n and then decrements q_e in a loop until it has the correct size.
Observing the number of times q_e is decremented through a control-flow
revealing side-channel reveals a bias in the most significant bits of
k. Depending on the curve this is either a negligible bias or a
significant bias large enough to reconstruct k with lattice reduction
methods. For SECP160R1, e.g., we find a bias of 15 bits. |
| Reference |
|
| CVSS |
| Base: | 4.1 |
| Impact: | 3.6 |
| Exploitability: | 0.5 |
|
| Pristup |
| Vektor | Složenost | Autentikacija |
| LOCAL |
HIGH |
HIGH |
|
| Impact |
| Povjerljivost | Cjelovitost | Dostupnost |
| HIGH |
NONE |
NONE |
|
| CVSS vektor |
CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:N/A:N |
| Zadnje važnije ažuriranje |
06-12-2025 - 01:03 |
| Objavljeno |
27-08-2024 - 19:15 |
