CVE-2021-42146: tinydtls (CVSS 7.5)

Description

An issue was discovered in Contiki-NG tinyDTLS through master branch 53a0d97. DTLS servers allow remote attackers to reuse the same epoch number within two times the TCP maximum segment lifetime, which is prohibited in RFC6347. This vulnerability allows remote attackers to obtain sensitive application (data of connected clients).

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CVSS v3.1 Score

7.5

HIGH

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

Weakness Type (CWE)

CWE-755 CWE-755

CWE-303 CWE-303

Affected Products

Vendor	Product	Versions
contiki-ng	tinydtls	All

References

Other References

https://seclists.org/fulldisclosure/2024/Jan/19 http://seclists.org/fulldisclosure/2024/Jan/19 https://seclists.org/fulldisclosure/2024/Jan/19

Frequently Asked Questions

What is CVE-2021-42146? +

An issue was discovered in Contiki-NG tinyDTLS through master branch 53a0d97. DTLS servers allow remote attackers to reuse the same epoch number within two times the TCP maximum segment lifetime, which is prohibited in RFC6347. This vulnerability allows remote attackers to obtain sensitive application (data of connected clients). It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2021-42146? +

CVE-2021-42146 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2021-42146? +

CVE-2021-42146 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-2021-42146? +

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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CVE-2021-42146