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CVE-2021-42143

Contiki-ng Tinydtls denial of service

9.1 CRITICALEPSS 0.81%
  1. Published24 Jan 2024

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 3.1 breakdown

Attack vectorNetwork
Attack complexityLow
Privileges requiredNone
User interactionNone
ScopeUnchanged
ConfidentialityHigh
IntegrityNone
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

Affected products

Contiki-ng Tinydtls≤ 2018-08-30

Remediation

No fixed version is recorded in the NVD data. Check the vendor advisory for the latest guidance.

References

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Frequently asked

Is CVE-2021-42143 being actively exploited?

CVE-2021-42143 is not in the CISA KEV catalog. Its EPSS exploit probability is 0.81%.

How severe is CVE-2021-42143?

CVE-2021-42143 has a CVSS 3.1 base score of 9.1, rated critical. EPSS estimates a 0.81% probability of exploitation.

Which products are affected by CVE-2021-42143?

Affected products include Contiki-ng Tinydtls.

How do I fix CVE-2021-42143?

Apply the vendor's patch or advisory guidance, then verify no affected versions remain across your devices.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2021-42143 against the real software inventory on every managed device, as each hourly inventory arrives. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

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Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.