Vulnerability in Arm Mbed Tls
CVE-2020-10932
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.
EPSS: 0.002 (16.2th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 4.7 (Medium). Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N.
Affected products
- Arm Mbed_tls
- Trustedfirmware Mbed_tls
- Debian Debian_linux — versions 10.0
- Fedoraproject Fedora — versions 31, 32
- N/a — versions n/a
Weakness classification (CWE)
Public proof-of-concept exploits
References
- cve@mitre.org (Vendor Advisory)
- cve@mitre.org (Vendor Advisory)
- cve@mitre.org (Release Notes)
- cve@mitre.org (vendor-advisory, Mailing List, Third Party Advisory)
- cve@mitre.org (vendor-advisory, Mailing List, Third Party Advisory)
- cve@mitre.org (mailing-list, Mailing List, Third Party Advisory)
Frequently asked questions
- What is CVE-2020-10932?
- CVE-2020-10932 is a medium-severity vulnerability in Arm Mbed Tls, classified under Observable Discrepancy. CVSS score: 4.7/10. Published 2020-04-15.
- How severe is CVE-2020-10932?
- Medium severity. CVSS v3 base score is 4.7 out of 10.
- Is CVE-2020-10932 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.