CVE-2021-43666 - Vulnerability Details - OpenCVE

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.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

Access Vector Network

Access Complexity Low

Authentication None

Confidentiality Impact None

Integrity Impact None

Availability Impact Partial

This CVE is not in the KEV list.

The EPSS score is 0.00152.

Exploitation poc

Automatable yes

Technical Impact partial

Vendors	Products
Arm	Mbed Tls
Debian	Debian Linux

Configuration 1 [-]

cpe:2.3:a:arm:mbed_tls:*:*:*:*:*:*:*:*

Configuration 2 [-]

cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*

No data.

No data.

Advisories

Source	ID	Title
Debian DLA	DLA-3249-1	mbedtls security update
Debian DLA	DLA-4236-1	mbedtls security update
EUVD	EUVD-2021-30578	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.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References

Link	Providers
https://github.com/ARMmbed/mbedtls/issues/5136
https://lists.debian.org/debian-lts-announce/2022/12/msg00036.html
https://lists.debian.org/debian-lts-announce/2025/06/msg00034.html

History

Tue, 02 Dec 2025 21:15:00 +0000

Type	Values Removed	Values Added
Weaknesses		CWE-130
Metrics		ssvc `{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Mon, 03 Nov 2025 20:30:00 +0000

Type	Values Removed	Values Added
References		https://lists.debian.org/debian-lts-announce/2025/06/msg00034.html

Mon, 14 Jul 2025 13:45:00 +0000

Type	Values Removed	Values Added
Metrics	epss `{'score': 0.00179}`	epss `{'score': 0.00111}`

MITRE

Status: PUBLISHED

Assigner: mitre

Published: 2022-03-24T00:00:00.000Z

Updated: 2025-12-02T20:51:13.720Z

Reserved: 2021-11-15T00:00:00.000Z

Link: CVE-2021-43666

Vulnrichment

Updated: 2025-11-03T19:26:30.089Z

NVD

Status : Modified

Published: 2022-03-24T18:15:08.333

Modified: 2025-12-02T21:15:49.503

Link: CVE-2021-43666

Redhat

No data.

OpenCVE Enrichment

No data.

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