CVE-2020-10932
What it is
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.
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of data exposure.
- Exploit odds
- 0.2% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.2% in the next 30 days (EPSS).
- Severity: 4.7 MEDIUM (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.2% · EPSS, next 30 days
- Weakness
- CWE-203
- Record status
- Modified
Affected
- Arm Mbed Tls < 2.7.15
- Trustedfirmware Mbed Tls < 2.16.6
- Fedoraproject Fedora 31
- Fedoraproject Fedora 32
- Debian Linux 10.0
Attack profile CVSS 3.1 · 4.7
- Attack vector
- Local
- Complexity
- High
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
Raw vector
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2020-10932.md and follow it. Check whether this project is affected by CVE-2020-10932. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://tls.mbed.org/tech-updates/security-advisories
- https://tls.mbed.org/tech-updates/security-advisories/mbedtls-security-advisory-2020-04
- https://tls.mbed.org/tech-updates/security-advisories
- https://tls.mbed.org/tech-updates/security-advisories/mbedtls-security-advisory-2020-04
References
- https://lists.debian.org/debian-lts-announce/2022/12/msg00036.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FCWN5HIF4CJ2LZTOMEBJ7Q4IMMV7ZU2V/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZNOS2IIBH5WNJXZUV546PY7666DE7Y3L/
- https://tls.mbed.org/tech-updates/releases/mbedtls-2.16.6-and-2.7.15-released
- https://tls.mbed.org/tech-updates/security-advisories
- https://tls.mbed.org/tech-updates/security-advisories/mbedtls-security-advisory-2020-04
- https://lists.debian.org/debian-lts-announce/2022/12/msg00036.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FCWN5HIF4CJ2LZTOMEBJ7Q4IMMV7ZU2V/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZNOS2IIBH5WNJXZUV546PY7666DE7Y3L/
- https://tls.mbed.org/tech-updates/releases/mbedtls-2.16.6-and-2.7.15-released
- https://tls.mbed.org/tech-updates/security-advisories
- https://tls.mbed.org/tech-updates/security-advisories/mbedtls-security-advisory-2020-04