CVE-2020-10932
Description
An issue was discovered in Arm Mbed TLS before 2.16.6 and 2.7.x before 2.7.15. An attacker that can get precise enough side-channel measurements can recover the long-term ECDSA private key by (1) reconstructing the projective coordinate of the result of scalar multiplication by exploiting side channels in the conversion to affine coordinates; (2) using an attack described by Naccache, Smart, and Stern in 2003 to recover a few bits of the ephemeral scalar from those projective coordinates via several measurements; and (3) using a lattice attack to get from there to the long-term ECDSA private key used for the signatures. Typically an attacker would have sufficient access when attacking an SGX enclave and controlling the untrusted OS.
How to fix
- arm mbed_tls2.7.15 or later
- trustedfirmware mbed_tls2.16.6 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| arm mbed_tls | 2.7.0 ≤ v < 2.7.15 | 2.7.15 |
| trustedfirmware mbed_tls | 2.16.0 ≤ v < 2.16.6 | 2.16.6 |
| fedoraproject fedora | 31, 32 | — |
| debian debian_linux | 10.0 | — |
Check your version
Choose the product and enter the version you run to see whether it falls in the affected range.
Attack Surface Management
See the assets tied to your domains, the technologies they run and known vulnerabilities in one list.