What is CVE-2021-42147?

CVE-2021-42147 is a critical-severity vulnerability in Contiki-Ng Tinydtls, classified under Out-of-bounds Read. CVSS score: 9.1/10. Published 2024-01-24.

How severe is CVE-2021-42147?

Critical severity. CVSS v3 base score is 9.1 out of 10.

Out-of-bounds Read in Contiki-Ng Tinydtls

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.

Vulnerability class: Buffer Overflow

Published 2024-01-24 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H.

EPSS exploit prediction

EPSS: 0.008 (56.1th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 56th percentile — 56.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.008 · newest: 0.008 · change: 0.000

Affected products

Contiki-Ng Tinydtls — versions 2018-08-30

Weakness classification (CWE)

CWE-125 — Out-of-bounds Read

References

seclists.org/fulldisclosure/2024/Jan/20 (Mailing List, Third Party Advisory)
af854a3a-2127-422b-91ae-364da2661108

Frequently asked questions

What is CVE-2021-42147?: CVE-2021-42147 is a critical-severity vulnerability in Contiki-Ng Tinydtls, classified under Out-of-bounds Read. CVSS score: 9.1/10. Published 2024-01-24.
How severe is CVE-2021-42147?: Critical severity. CVSS v3 base score is 9.1 out of 10.