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CVE-2021-42143

Published: Jan 24, 2024Updated: Jun 20, 2025 Sources: CVE List NVDCWE-835
NVD MITRE
9.1CVSSCRITICAL
EPSS Score
0.8%
Top 47.8%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
No Fix Available

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.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:HI:NA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:NIntegrity
None
A:HAvailability
High
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Weaknesses

CWE-835

Affected Products

tinydtlscontiki-ng
Embedded
Operating Systems / rtos-embedded-os
n/an/a
contiki-ngoss-projectOperating Systemsaka contiki-ng., tinydtls

Attack Graph

Products CVE Techniques Tactics

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Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.

MITRE ATT&CK

1 technique
Impact
View detailed technique mapping

References

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

Timeline

Published
Jan 24, 2024
Last Updated
Jun 20, 2025

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