ARM Mbed TLS up to 2.16.6/2.22.x Modular Exponentiation information exposure

CVSS Meta Temp Score
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CTI Interest Score
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3.8$0-$5k0.00

Summaryinfo

A vulnerability identified as problematic has been detected in ARM Mbed TLS up to 2.16.6/2.22.x. Impacted is an unknown function of the component Modular Exponentiation Handler. Performing a manipulation results in information exposure. This vulnerability is reported as CVE-2020-36421. Moreover, an exploit is present. You should upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, was found in ARM Mbed TLS up to 2.16.6/2.22.x. This affects some unknown functionality of the component Modular Exponentiation Handler. The manipulation with an unknown input leads to a information exposure vulnerability. CWE is classifying the issue as CWE-203. The product behaves differently or sends different responses under different circumstances in a way that is observable to an unauthorized actor, which exposes security-relevant information about the state of the product, such as whether a particular operation was successful or not. This is going to have an impact on confidentiality.

The weakness was disclosed 07/19/2021. This vulnerability is uniquely identified as CVE-2020-36421. Technical details are unknown but a public exploit is available. The attack technique deployed by this issue is T1592 according to MITRE ATT&CK.

The exploit is shared for download at github.com. It is declared as proof-of-concept. The vulnerability scanner Nessus provides a plugin with the ID 250224 (Linux Distros Unpatched Vulnerability : CVE-2020-36421), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 2.16.7 or 2.23.0 eliminates this vulnerability. The upgrade is hosted for download at github.com.

The vulnerability is also documented in the vulnerability database at Tenable (250224). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 3.9
VulDB Meta Temp Score: 3.8

VulDB Base Score: 2.6
VulDB Temp Score: 2.4
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.3
NVD Vector: 🔍

CVSSv2info

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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Information exposure
CWE: CWE-203 / CWE-200 / CWE-284
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 250224
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2020-36421

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Mbed TLS 2.16.7/2.23.0

Timelineinfo

07/19/2021 🔍
07/19/2021 +0 days 🔍
07/19/2021 +0 days 🔍
12/03/2025 +1598 days 🔍

Sourcesinfo

Status: Confirmed

CVE: CVE-2020-36421 (🔍)
GCVE (CVE): GCVE-0-2020-36421
GCVE (VulDB): GCVE-100-178887
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 07/19/2021 21:37
Updated: 12/03/2025 19:13
Changes: 07/19/2021 21:37 (41), 07/22/2021 10:01 (2), 08/16/2025 19:29 (16), 12/03/2025 19:13 (19)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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