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).
History

No history.

cve-icon MITRE

Status: PUBLISHED

Assigner: mitre

Published: 2021-08-23T00:00:00

Updated: 2024-08-04T17:30:08.378Z

Reserved: 2021-08-23T00:00:00

Link: CVE-2020-36477

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Analyzed

Published: 2021-08-23T02:15:07.043

Modified: 2023-01-13T19:59:16.777

Link: CVE-2020-36477

cve-icon Redhat

No data.