CVE-2021-42141: tinydtls — Fix

Description

An issue was discovered in Contiki-NG tinyDTLS through 2018-08-30. One incorrect handshake could complete with different epoch numbers in the packets Client_Hello, Client_key_exchange, and Change_cipher_spec, which may cause denial of service.

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CVSS v3.1 Score

9.8

CRITICAL

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

Weakness Type (CWE)

CWE-755 CWE-755

Affected Products

Vendor	Product	Versions
contiki-ng	tinydtls	< 2018-08-30

References

Advisories & Patches

https://github.com/contiki-ng/tinydtls/issues/27 https://github.com/contiki-ng/tinydtls/issues/27

Other References

http://packetstormsecurity.com/files/176625/Contiki-NG-tinyDTLS-Denial-Of-Service.html https://seclists.org/fulldisclosure/2024/Jan/14 http://packetstormsecurity.com/files/176625/Contiki-NG-tinyDTLS-Denial-Of-Service.html http://seclists.org/fulldisclosure/2024/Jan/14 https://seclists.org/fulldisclosure/2024/Jan/14

Frequently Asked Questions

What is CVE-2021-42141? +

An issue was discovered in Contiki-NG tinyDTLS through 2018-08-30. One incorrect handshake could complete with different epoch numbers in the packets Client_Hello, Client_key_exchange, and Change_cipher_spec, which may cause denial of service. It has a CVSS v3.1 base score of 9.8 (CRITICAL).

How severe is CVE-2021-42141? +

CVE-2021-42141 has a CVSS v3.1 score of 9.8 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately.

What products are affected by CVE-2021-42141? +

CVE-2021-42141 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-2021-42141? +

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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