CVE-2019-18222 Information disclosure in n/a

Medium 4.7 Published 23 Jan 2020 Updated 5 Aug 2024

A local attacker can recover private keys from Mbed TLS ECDSA signatures via side-channel attacks due to improper scalar reduction.

Exploited in the wild: Not known
Login needed: Any signed-in user
Attackable: Local or same network only
Victim action needed: Not needed
Fix: Available

What is CVE-2019-18222?

CVE-2019-18222 is a medium-severity vulnerability in Arm Mbed Tls, published on 23 Jan 2020. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

The ECDSA signature implementation in ecdsa.c in Arm Mbed Crypto 2.1 and Mbed TLS through 2.19.1 does not reduce the blinded scalar before computing the inverse, which allows a local attacker to recover the private key via side-channel attacks.

Weakness: CWE-203

Which versions are affected by CVE-2019-18222?

It affects 4 products.

Products include Arm Mbed Crypto, Arm Mbed Tls, Debian Debian Linux, Fedoraproject Fedora.

How do I fix CVE-2019-18222?

Upgrade to a fixed version.

Is CVE-2019-18222 being exploited?

There is no known exploitation of CVE-2019-18222 in the wild and no public exploit code.

All Arm Mbed Tls vulnerabilities

Sources

Also known as ALPINE-CVE-2019-18222, DEBIAN-CVE-2019-18222, GHSA-fpgh-hvp5-cqc2, JLSEC-2025-199, UBUNTU-CVE-2019-18222.