CVE-2024-45159: Trustedfirmware Mbed Tls vulnerability (CVSS 9.8)

Description

An issue was discovered in Mbed TLS 3.x before 3.6.1. With TLS 1.3, when a server enables optional authentication of the client, if the client-provided certificate does not have appropriate values in if keyUsage or extKeyUsage extensions, then the return value of mbedtls_ssl_get_verify_result() would incorrectly have the MBEDTLS_X509_BADCERT_KEY_USAGE and MBEDTLS_X509_BADCERT_KEY_USAGE bits clear. As a result, an attacker that had a certificate valid for uses other than TLS client authentication would nonetheless be able to use it for TLS client authentication. Only TLS 1.3 servers were affected, and only with optional authentication (with required authentication, the handshake would be aborted with a fatal alert).

CVSS 3.1 breakdown

Attack vectorNetwork

Attack complexityLow

Privileges requiredNone

User interactionNone

ScopeUnchanged

ConfidentialityHigh

IntegrityHigh

AvailabilityHigh

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

Trustedfirmware Mbed Tls≥ 3.2.0 < 3.6.1

Remediation

Fixed in

Trustedfirmware Mbed Tls≥ 3.6.1

Patch & vendor advisories

https://mbed-tls.readthedocs.io/en/latest/security-advisories/mbedtls-security-advisory-2024-08-3/

References

https://github.com/Mbed-TLS/mbedtls/releases/Release Notes
https://mbed-tls.readthedocs.io/en/latest/security-advisories/Issue Tracking
https://mbed-tls.readthedocs.io/en/latest/security-advisories/mbedtls-security-advisory-2024-08-3/Vendor Advisory

Related CVEs

Recent high-severity vulnerabilities sharing a weakness type.

Frequently asked

Is CVE-2024-45159 being actively exploited?

CVE-2024-45159 is not in the CISA KEV catalog. Its EPSS exploit probability is 0.39%.

How severe is CVE-2024-45159?

CVE-2024-45159 has a CVSS 3.1 base score of 9.8, rated critical. EPSS estimates a 0.39% probability of exploitation.

Which products are affected by CVE-2024-45159?

Affected products include Trustedfirmware Mbed Tls.

How do I fix CVE-2024-45159?

Upgrade affected software to a fixed version, for example Trustedfirmware Mbed Tls 3.6.1 or later, then confirm no affected versions remain in your inventory.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2024-45159 against the real software inventory on every managed device, every day. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

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