CVE-2021-42143

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Published Jan 24, 2024 CVSS 3.1 · 9.1 Critical EPSS < 1% KEV · Not listed

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.

Affected Products

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 solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

No advisories available

Metrics

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.

Exploit prediction score: < 1% (0.812% probability within 30 days)

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

Jun 20, 2025 8:15 PM Scoring metrics updated View changes

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

Nov 22, 2024 12:00 PM Added references View changes

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

Subscriptions

Contiki-ng Tinydtls

Weaknesses

CWE-835

Sources

CVE record Updated: Jun 20, 2025, 7:16 PM

Status: PUBLISHED
Assigner: mitre
Published: Jan 24, 2024, 12:00 AM
Updated: Jun 20, 2025, 7:16 PM
Reserved: Oct 11, 2021, 12:00 AM

View source JSON

Vulnrichment Updated: Aug 4, 2024, 3:30 AM

Updated: Aug 4, 2024, 3:30 AM

NVD Updated: Jun 17, 2026, 4:09 AM

Status: Modified
Published: Jan 24, 2024, 6:15 PM
Modified: Jun 17, 2026, 4:09 AM

View source JSON

Red Hat No data

No data.

OpenCVE enrichment No data

No data.

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