Upstream information
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).SUSE information
Overall state of this security issue: Does not affect SUSE products
This issue is currently rated as having moderate severity.
| CVSS detail | National Vulnerability Database |
|---|---|
| Base Score | 4.3 |
| Vector | AV:N/AC:M/Au:N/C:N/I:P/A:N |
| Access Vector | Network |
| Access Complexity | Medium |
| Authentication | None |
| Confidentiality Impact | None |
| Integrity Impact | Partial |
| Availability Impact | None |
| CVSS detail | National Vulnerability Database |
|---|---|
| Base Score | 5.9 |
| Vector | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N |
| Attack Vector | Network |
| Attack Complexity | High |
| Privileges Required | None |
| User Interaction | None |
| Scope | Unchanged |
| Confidentiality Impact | None |
| Integrity Impact | High |
| Availability Impact | None |
| CVSSv3 Version | 3.1 |
SUSE Timeline for this CVE
CVE page created: Mon Aug 23 12:00:05 2021CVE page last modified: Mon Oct 6 19:27:46 2025