Security advisory

{
  "id": "c7db7add33b3bfdbc3e64480df73238d388a19440a15e726ef7b19a01ef94264",
  "url": "https://osv.dev/vulnerability/CVE-2021-43666",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2021-43666",
    "summary": "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.",
    "evidence": "osv:CVE-2021-43666",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2021-43666",
      "aliases": [
        "CVE-2021-43666"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/Mbed-TLS/mbedtls",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "last_affected": "8df2f8e7b9c7bb9390ac74bb7bace27edca81a2b"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:arm:mbed_tls:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "last_affected": "3.0.0"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v3.0.0",
            "mbedtls-3.0.0",
            "v2.26.0",
            "mbedtls-2.26.0",
            "v2.24.0",
            "mbedtls-2.24.0",
            "mbedtls-2.19.1",
            "mbedtls-2.22.0d0",
            "mbedtls-2.21.0",
            "mbedtls-2.20.0",
            "mbedtls-2.20.0d0",
            "mbedtls-2.19.0d2",
            "mbedtls-2.19.0",
            "mbedtls-2.19.0d1",
            "mbedtls-2.16.0",
            "mbedtls-2.14.0",
            "mbedtls-2.13.1",
            "mbedtls-2.13.0",
            "mbedtls-2.12.0",
            "mbedtls-2.11.0",
            "mbedtls-2.10.0",
            "mbedtls-2.7.0",
            "mbedtls-2.9.0",
            "mbedtls-2.8.0",
            "mbedtls-2.8.0-rc1",
            "mbedtls-2.7.0-rc1",
            "mbedtls-2.6.0",
            "mbedtls-2.6.0-rc1",
            "mbedtls-2.5.1",
            "mbedtls-2.5.0",
            "mbedtls-2.4.0",
            "mbedtls-2.2.1",
            "yotta-2.3.1",
            "mbedtls-2.3.0",
            "mbedtls-2.2.0",
            "mbedos-release-15-11",
            "mbedos-techcon-oob2",
            "mbedtls-2.1.2",
            "mbedtls-2.1.0",
            "mbedtls-2.1.1",
            "beta-oob-2",
            "mbedtls-2.0.0",
            "polarssl-1.3.9",
            "polarssl-1.3.8",
            "polarssl-1.3.7",
            "polarssl-1.3.6",
            "polarssl-1.3.5",
            "polarssl-1.3.4",
            "polarssl-1.3.3",
            "polarssl-1.3.2",
            "polarssl-1.3.1",
            "polarssl-1.3.0",
            "polarssl-1.3.0-rc0",
            "polarssl-1.2.6",
            "polarssl-1.2.5",
            "polarssl-1.2.4",
            "polarssl-1.2.2",
            "polarssl-1.2.1",
            "polarssl-1.2.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-43666.json"
          }
        }
      ],
      "modified": "2026-10-20T10:54:08.912481044Z",
      "provider": "osv",
      "references": [
        "https://lists.debian.org/debian-lts-announce/2025/06/msg00034.html",
        "https://lists.debian.org/debian-lts-announce/2022/12/msg00036.html",
        "https://github.com/ARMmbed/mbedtls/issues/5136"
      ],
      "provider_metadata": {
        "unresolved_ranges": [
          {
            "cpes": [
              "cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*"
            ],
            "vendor_product": "debian:debian_linux",
            "extracted_events": [
              {
                "range": [
                  {
                    "introduced": "10.0"
                  },
                  {
                    "last_affected": "10.0"
                  }
                ],
                "source": "CPE_STRING"
              }
            ]
          }
        ]
      }
    },
    "related_cves": [
      {
        "value": "CVE-2021-43666",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 384899,
  "published_at": "2022-03-24T18:15:08.333+00:00"
}