CVE-2020-36421 - Vulnerability Details - OpenCVE

An issue was discovered in Arm Mbed TLS before 2.23.0. Because of a side channel in modular exponentiation, an RSA private key used in a secure enclave could be disclosed.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact Low

Integrity Impact None

Availability Impact None

User Interaction None

No CVSS v3.0

Access Vector Network

Access Complexity Low

Authentication None

Confidentiality Impact Partial

Integrity Impact None

Availability Impact None

This CVE is not in the KEV list.

The EPSS score is 0.0019.

Exploitation none

Automatable yes

Technical Impact partial

Vendors	Products
Arm Subscribe	Mbed Tls Subscribe
Debian Subscribe	Debian Linux Subscribe

Configuration 1 [-]

OR	cpe:2.3:a:arm:mbed_tls::::::::
	cpe:2.3:a:arm:mbed_tls::::::::

Configuration 2 [-]

cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*

No data.

No data.

Advisories

Source	ID	Title
Debian DLA	DLA-3249-1	mbedtls security update
EUVD	EUVD-2020-23949	An issue was discovered in Arm Mbed TLS before 2.23.0. Because of a side channel in modular exponentiation, an RSA private key used in a secure enclave could be disclosed.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References

Link	Providers
https://bugs.gentoo.org/730752
https://github.com/ARMmbed/mbedtls/issues/3394
https://github.com/ARMmbed/mbedtls/releases/tag/v2.16.7
https://github.com/ARMmbed/mbedtls/releases/tag/v2.23.0
https://lists.debian.org/debian-lts-announce/2022/12/msg00036.html

History

Wed, 03 Dec 2025 16:15:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Projects

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MITRE

Status: PUBLISHED

Assigner: mitre

Published: 2021-07-19T00:00:00.000Z

Updated: 2025-12-03T16:11:10.708Z

Reserved: 2021-07-19T00:00:00.000Z

Link: CVE-2020-36421

Vulnrichment

Updated: 2024-08-04T17:30:06.804Z

NVD

Status : Modified

Published: 2021-07-19T17:15:11.133

Modified: 2025-12-03T16:15:53.017

Link: CVE-2020-36421

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-203

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