CVE-2020-10932
MEDIUM4.7EPSS 0.04%Published: 4/15/2020Modified: 12/3/2025
Also known as:ALPINE-CVE-2020-10932DEBIAN-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.
Affected packages (2)
- Alpine/mbedtlsfrom 0, < 2.16.6-r0
- Debian/mbedtlsfrom 0, < 2.16.9-0.1
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | MEDIUM4.7 | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N |