CVE-2021-42143 - Vulnerability Details - OpenCVE

Description

An issue was discovered in Contiki-NG tinyDTLS through master branch 53a0d97. An infinite loop bug exists during the handling of a ClientHello handshake message. This bug allows remote attackers to cause a denial of service by sending a malformed ClientHello handshake message with an odd length of cipher suites, which triggers an infinite loop (consuming all resources) and a buffer over-read that can disclose sensitive information.

Published: 2024-01-24

Score: 9.1 Critical

EPSS: < 1% Very Low

KEV: No

Impact:

Action:

Analysis

Analysis and contextual insights are available on OpenCVE Cloud.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

n/a

n/a

affected

Version	Status	Constraints
`n/a`	affected	—

Configuration 1 [-]

cpe:2.3:a:contiki-ng:tinydtls:*:*:*:*:*:*:*:*

No data.

No data available yet.

Remediation

No vendor fix or workaround currently provided.

Additional remediation guidance may be available on OpenCVE Cloud.

Tracking

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Advisories

No advisories yet.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact High

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

The EPSS score is 0.00354.

Exploitation none

Automatable no

Technical Impact partial

References

Link	Providers
http://seclists.org/fulldisclosure/2024/Jan/16
https://seclists.org/fulldisclosure/2024/Jan/16

History

Fri, 20 Jun 2025 20:15:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Fri, 22 Nov 2024 12:00:00 +0000

Type	Values Removed	Values Added
References		http://seclists.org/fulldisclosure/2024/Jan/16

Subscriptions

Contiki-ng Tinydtls

MITRE

Status: PUBLISHED

Assigner: mitre

Published: 2024-01-24T00:00:00.000Z

Updated: 2025-06-20T19:16:00.614Z

Reserved: 2021-10-11T00:00:00.000Z

Link: CVE-2021-42143

Vulnrichment

Updated: 2024-08-04T03:30:37.578Z

NVD

Status : Modified

Published: 2024-01-24T18:15:08.080

Modified: 2025-06-20T20:15:21.900

Link: CVE-2021-42143

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-835

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