CVE-2020-36477

medium

Description

An issue was discovered in Mbed TLS before 2.24.0. The verification of X.509 certificates when matching the expected common name (the cn argument of mbedtls_x509_crt_verify) with the actual certificate name is mishandled: when the subjecAltName extension is present, the expected name is compared to any name in that extension regardless of its type. This means that an attacker could impersonate a 4-byte or 16-byte domain by getting a certificate for the corresponding IPv4 or IPv6 address (this would require the attacker to control that IP address, though).

References

https://security.gentoo.org/glsa/202301-08

https://github.com/ARMmbed/mbedtls/releases/tag/v2.24.0

https://github.com/ARMmbed/mbedtls/issues/3498

Details

Source: Mitre, NVD

Published: 2021-08-23

Updated: 2023-01-13

Risk Information

CVSS v2

Base Score: 4.3

Vector: CVSS2#AV:N/AC:M/Au:N/C:N/I:P/A:N

Severity: Medium

CVSS v3

Base Score: 5.9

Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N

Severity: Medium