CVE-2021-42147

CRITICAL

Published Jan 24, 2024 Modified May 30, 2025 CWE-125

Description

Buffer over-read vulnerability in the dtls_sha256_update function in Contiki-NG tinyDTLS through master branch 53a0d97 allows remote attackers to cause a denial of service via crafted data packet.

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CVSS v3.1 Score

9.1

CRITICAL

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

Weakness Type (CWE)

CWE-125 Out-of-bounds Read

Affected Products

Vendor	Product	Versions
contiki-ng	tinydtls	All

References

Other References

https://seclists.org/fulldisclosure/2024/Jan/20 http://seclists.org/fulldisclosure/2024/Jan/20 https://seclists.org/fulldisclosure/2024/Jan/20

Frequently Asked Questions

What is CVE-2021-42147? +

Buffer over-read vulnerability in the dtls_sha256_update function in Contiki-NG tinyDTLS through master branch 53a0d97 allows remote attackers to cause a denial of service via crafted data packet. It has a CVSS v3.1 base score of 9.1 (CRITICAL).

How severe is CVE-2021-42147? +

CVE-2021-42147 has a CVSS v3.1 score of 9.1 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately.

What products are affected by CVE-2021-42147? +

CVE-2021-42147 affects products from contiki-ng, specifically: tinydtls. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2021-42147? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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