2020-36426 | ARM Mbed TLS mbedtls_x509_crl_parse_der buffer overflow

By Max On Jul 22, 2021

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5.3	$0-$5k	0.29

A vulnerability was found in ARM Mbed TLS up to 2.7.16/2.16.7/2.23.x. It has been classified as critical. Affected is the function mbedtls_x509_crl_parse_der. The manipulation with an unknown input leads to a memory corruption vulnerability. CWE is classifying the issue as CWE-120. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

An issue was discovered in Arm Mbed TLS before 2.24.0. mbedtls_x509_crl_parse_der has a buffer over-read (of one byte).

The weakness was published 07/19/2021. The advisory is available at bugs.gentoo.org. This vulnerability is traded as CVE-2020-36426 since 07/19/2021. The exploitability is told to be easy. Access to the local network is required for this attack. The requirement for exploitation is a authentication. Technical details are known, but there is no available exploit.

Upgrading to version 2.7.17, 2.16.8 or 2.24.0 eliminates this vulnerability.

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