CVE-2021-43666
CVSS v3
7.5
HIGH
EPSS Score
2.1 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
A Denial of Service vulnerability exists in mbed TLS 3.0.0 and earlier in the mbedtls_pkcs12_derivation function when an input password's length is 0.
Technical details
- Published
- 2022-03-24
Frequently asked questions
What is CVE-2021-43666?
A Denial of Service vulnerability exists in mbed TLS 3.0.0 and earlier in the mbedtls_pkcs12_derivation function when an input password's length is 0.
Is CVE-2021-43666 actively exploited?
Active exploitation of CVE-2021-43666 has not been confirmed. Its EPSS score was 2.1% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2021-43666?
CVE-2021-43666 has a CVSS v3 base score of 7.5 (HIGH severity).
Is CVE-2021-43666 affecting your environment?
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