What is CVE-2021-34430?

CVE-2021-34430 is a high-severity vulnerability in Eclipse Tinydtls, classified under Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG). CVSS score: 7.5/10. Published 2021-07-08.

How severe is CVE-2021-34430?

High severity. CVSS v3 base score is 7.5 out of 10.

Vulnerability in Eclipse Tinydtls

CVE-2021-34430

Eclipse TinyDTLS through 0.9-rc1 relies on the rand function in the C library, which makes it easier for remote attackers to compute the master key and then decrypt DTLS traffic.

Published 2021-07-08 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.010 (62.8th percentile), scored 2026-10-01.

Low probability of exploitation in the next 30 days, but still tracked. 63rd percentile — 62.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.010 · newest: 0.010 · change: 0.000

Affected products

Eclipse Tinydtls — versions 0.9
The Eclipse Foundation Tinydtls — versions unspecified

Weakness classification (CWE)

References

bugs.eclipse.org/bugs/show_bug.cgi (Exploit, Issue Tracking, Vendor Advisory)

Frequently asked questions

What is CVE-2021-34430?: CVE-2021-34430 is a high-severity vulnerability in Eclipse Tinydtls, classified under Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG). CVSS score: 7.5/10. Published 2021-07-08.
How severe is CVE-2021-34430?: High severity. CVSS v3 base score is 7.5 out of 10.