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Public proof of conceptFix available

CVE-2021-43666

A public proof of concept exists; no exploitation attested.

  • Published2022-03-24
  • WeaknessCWE-130

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

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.

Timeline

dates in UTC
  1. 2022-03-2418:15CVE publishedNVD

Versions per branch

NVD
Arm mbed tls
BranchAffectedFixed in
3.0≤ 3.0.0no fix published
Debian debian linux
BranchAffectedFixed in
10.0= 10.0no fix published

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Distribution builds and vendor advisories

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Packages

  • mbedtlsUbuntu:Pro:20.04:LTSall versions · no fixed version listed
  • mbedtlsUbuntu:Pro:18.04:LTSall versions · no fixed version listed
  • mbedtlsUbuntu:16.04:LTSall versions · no fixed version listed
  • mbedtlsDebian:14all versions · fixed in 2.28.0-1
  • mbedtlsDebian:13all versions · fixed in 2.28.0-1
  • mbedtlsDebian:12all versions · fixed in 2.28.0-1
  • mbedtlsDebian:11all versions · fixed in 2.16.9-0.1+deb11u1
  • mbedtlsDebian:10all versions · fixed in 2.16.9-0~deb10u1

Vendor advisories

  • CVE-2021-43666 Red Hat Product Security

    Fedora: A Denial of Service vulnerability exists in mbed TLS 3.0.0 and earlier in the mbedtls_pkcs12

  • ICSA-24-046-11 CISA11 known affected

    Siemens SCALANCE XCM-/XRM-300

    SCALANCE XCH328 (6GK5328-4TS01-2EC2) · SCALANCE XCM324 (6GK5324-8TS01-2AC2) · SCALANCE XCM328 (6GK5328-4TS01-2AC2) · +8 more

  • SSA-806742 Siemens ProductCERT11 known affected

    SSA-806742: Multiple Vulnerabilities in SCALANCE XCM-/XRM-300 before V2.4

    SCALANCE XCH328 (6GK5328-4TS01-2EC2) · SCALANCE XCM324 (6GK5324-8TS01-2AC2) · SCALANCE XCM328 (6GK5328-4TS01-2AC2) · +8 more

Full record on NVD

Fix

  1. Vendor fix Siemens ProductCERT SSA-806742 · 10 productsUpdate to V2.4 or later version
  2. Vendor fix CISA ICSA-24-046-11 · 10 productsUpdate to V2.4 or later version

Detection

Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof of concept
Metasploit modules
none listed
Metasploit Framework

Sources

Identifiers

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Published
2022-03-24
Last Modified
2026-06-17
NVD status
Modified
GitHub Advisory
GHSA-cgwh-hfr7-38m2

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?

A proof-of-concept exploit exists for CVE-2021-43666, but active exploitation has not been confirmed at this time.

What is the CVSS score for CVE-2021-43666?

CVE-2021-43666 has a CVSS v3 base score of 7.5 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

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Sources for this record