CVE-2021-43666
HighPublic PoC
Published: 24 March 2022
Published
24 March 2022
Modified
02 December 2025
KEV Added
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Patch
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CVSS Score v3.1
7.5
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score
0.0071
72.8th percentile
Risk Priority
15
60% EPSS · 20% KEV · 20% CVSS
Summary
CVE-2021-43666 is a high-severity Improper Handling of Length Parameter Inconsistency (CWE-130) vulnerability in Arm Mbed Tls. Its CVSS base score is 7.5 (High).
Operationally, ranked in the top 27.2% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2021-30578
Vulnerability details
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.
- CWE(s)
Related Threats
No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.
Affected Assets
arm
mbed tls
≤ 3.0.0
debian
debian linux
10.0
Mitigating Controls
No mitigating controls mapped yet. The per-CVE control annotator has not reached this CVE.