CVE-2020-36426: High severity mbed tls vulnerability

Published Jul 19, 2021
·
Updated

An issue was discovered in Arm Mbed TLS before 2.24.0. mbedtlsx509crlparseder has a buffer over-read (of one byte).

Affected Software

4 affected components
Arm mbed TLS<2.7.17
Arm mbed TLS>=2.8.0<2.16.8
Arm mbed TLS>=2.17.0<2.24.0
Debian Debian Linux=10.0

Event History

Jul 19, 2021
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
Description
Sep 4, 2025
Data Sourced
via Microsoft·03:23 AM
DescriptionSeverityWeakness
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Frequently Asked Questions

1

What is CVE-2020-36426?

CVE-2020-36426 is a vulnerability discovered in Arm Mbed TLS before version 2.24.0, which allows a buffer over-read of one byte in the mbedtls_x509_crl_parse_der function.

2

What is the severity of CVE-2020-36426?

The severity of CVE-2020-36426 is high with a CVSS score of 7.5.

3

Which software is affected by CVE-2020-36426?

The affected software includes Arm Mbed TLS versions up to and excluding 2.7.17, versions between 2.8.0 and 2.16.8 (inclusive), and versions between 2.17.0 and 2.24.0 (inclusive). Debian Linux version 10.0 is also affected.

4

How can I fix CVE-2020-36426?

To fix CVE-2020-36426, update to Arm Mbed TLS version 2.24.0 or later, which contains a fix for the vulnerability.

5

Are there any references available for CVE-2020-36426?

Yes, you can refer to the following links for more information: [Gentoo Bug Tracker](https://bugs.gentoo.org/740108), [Arm Mbed TLS Release v2.16.8](https://github.com/ARMmbed/mbedtls/releases/tag/v2.16.8), [Arm Mbed TLS Release v2.24.0](https://github.com/ARMmbed/mbedtls/releases/tag/v2.24.0).

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