#VU26020 Cryptographic issues in mbed TLS and mbed Crypto - CVE-2019-18222

Vulnerability identifier: #VU26020

Vulnerability risk: Low

CVSSv4.0: 1.1 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2019-18222

CWE-ID: CWE-310

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
mbed TLS
Universal components / Libraries / Libraries used by multiple products
mbed Crypto
Universal components / Libraries / Libraries used by multiple products

Vendor: ARM

Description

The vulnerability allows an attacker to gain access to sensitive information.

the vulnerability exists due to 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.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

mbed TLS: 2.7.0 - 2.7.12, 2.19.0 - 2.19.1

mbed Crypto: 2.0.0d0 - 3.0.0

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External links
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/A3GWQNONS7GRORXZJ7MOJFUEJ2ZJ4OUW/
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/NGDACU65MYZXXVPQP2EBHUJGOR4RWLVY/
https://tls.mbed.org/tech-updates/security-advisories
https://tls.mbed.org/tech-updates/security-advisories/mbedtls-security-advisory-2019-12

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.