ubuntu-cve-2026-40253
Vulnerability from osv_ubuntu
Published
2026-04-16 23:16
Modified
2026-05-20 15:27
Summary
Details

openCryptoki is a PKCS#11 library and provides tooling for Linux and AIX. In versions 3.26.0 and below, the BER/DER decoding functions in the shared common library (asn1.c) accept a raw pointer but no buffer length parameter, and trust attacker-controlled BER length fields without validating them against actual buffer boundaries. All primitive decoders are affected: ber_decode_INTEGER, ber_decode_SEQUENCE, ber_decode_OCTET_STRING, ber_decode_BIT_STRING, and ber_decode_CHOICE. Additionally, ber_decode_INTEGER can produce integer underflows when the encoded length is zero. An attacker supplying a malformed BER-encoded cryptographic object through PKCS#11 operations such as C_CreateObject or C_UnwrapKey, token loading from disk, or remote backend communication can trigger out-of-bounds reads. This affects all token backends (Soft, ICA, CCA, TPM, EP11, ICSF) since the vulnerable code is in the shared common library. A patch is available thorugh commit ed378f463ef73364c89feb0fc923f4dc867332a3.

Severity
6.8 (Medium)
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H
6.1 (Medium)
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H
N/A (UNKNOWN)
medium
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libopencryptoki0",
            "binary_version": "3.4.1+dfsg-1ubuntu4.1"
          },
          {
            "binary_name": "opencryptoki",
            "binary_version": "3.4.1+dfsg-1ubuntu4.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:16.04:LTS",
        "name": "opencryptoki",
        "purl": "pkg:deb/ubuntu/opencryptoki@3.4.1+dfsg-1ubuntu4.1?arch=source\u0026distro=xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.3.1+dfsg-3ubuntu5",
        "3.4.1+dfsg-1ubuntu1",
        "3.4.1+dfsg-1ubuntu2",
        "3.4.1+dfsg-1ubuntu3",
        "3.4.1+dfsg-1ubuntu4",
        "3.4.1+dfsg-1ubuntu4.1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libopencryptoki0",
            "binary_version": "3.9.0+dfsg-0ubuntu1.4"
          },
          {
            "binary_name": "opencryptoki",
            "binary_version": "3.9.0+dfsg-0ubuntu1.4"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:18.04:LTS",
        "name": "opencryptoki",
        "purl": "pkg:deb/ubuntu/opencryptoki@3.9.0+dfsg-0ubuntu1.4?arch=source\u0026distro=bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.7.0+dfsg-4",
        "3.8.1+dfsg-2",
        "3.8.1+dfsg-3",
        "3.8.2+dfsg-0ubuntu1",
        "3.9.0+dfsg-0ubuntu1",
        "3.9.0+dfsg-0ubuntu1.1",
        "3.9.0+dfsg-0ubuntu1.2",
        "3.9.0+dfsg-0ubuntu1.3",
        "3.9.0+dfsg-0ubuntu1.4"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libopencryptoki0",
            "binary_version": "3.13.0+dfsg-0ubuntu5.2"
          },
          {
            "binary_name": "opencryptoki",
            "binary_version": "3.13.0+dfsg-0ubuntu5.2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "opencryptoki",
        "purl": "pkg:deb/ubuntu/opencryptoki@3.13.0+dfsg-0ubuntu5.2?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.11.1+dfsg-0ubuntu2",
        "3.11.1+dfsg-0ubuntu3",
        "3.12.1+dfsg-0ubuntu1",
        "3.13.0+dfsg-0ubuntu4",
        "3.13.0+dfsg-0ubuntu5",
        "3.13.0+dfsg-0ubuntu5.1",
        "3.13.0+dfsg-0ubuntu5.2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libopencryptoki0",
            "binary_version": "3.17.0+dfsg+20220202.b40982e-0ubuntu1.2"
          },
          {
            "binary_name": "opencryptoki",
            "binary_version": "3.17.0+dfsg+20220202.b40982e-0ubuntu1.2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "opencryptoki",
        "purl": "pkg:deb/ubuntu/opencryptoki@3.17.0+dfsg+20220202.b40982e-0ubuntu1.2?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.16.0+dfsg-0ubuntu1",
        "3.16.0+dfsg-0ubuntu2",
        "3.16.0+dfsg-0ubuntu3",
        "3.17.0+dfsg+20220202.b40982e-0ubuntu1",
        "3.17.0+dfsg+20220202.b40982e-0ubuntu1.1",
        "3.17.0+dfsg+20220202.b40982e-0ubuntu1.2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libopencryptoki0",
            "binary_version": "3.23.0+dfsg-0ubuntu3"
          },
          {
            "binary_name": "opencryptoki",
            "binary_version": "3.23.0+dfsg-0ubuntu3"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "opencryptoki",
        "purl": "pkg:deb/ubuntu/opencryptoki@3.23.0+dfsg-0ubuntu3?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.21.0+dfsg-0ubuntu1",
        "3.21.0+dfsg-0ubuntu2",
        "3.22.0+dfsg-0ubuntu1",
        "3.23.0+dfsg-0ubuntu1",
        "3.23.0+dfsg-0ubuntu2",
        "3.23.0+dfsg-0ubuntu3"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libopencryptoki0",
            "binary_version": "3.25.0+dfsg-0ubuntu1"
          },
          {
            "binary_name": "opencryptoki",
            "binary_version": "3.25.0+dfsg-0ubuntu1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:25.10",
        "name": "opencryptoki",
        "purl": "pkg:deb/ubuntu/opencryptoki@3.25.0+dfsg-0ubuntu1?arch=source\u0026distro=questing"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.24.0+git20250128.0462717+dfsg-0ubuntu1",
        "3.25.0+dfsg-0ubuntu1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libopencryptoki0",
            "binary_version": "3.26.0+dfsg-0ubuntu1"
          },
          {
            "binary_name": "opencryptoki",
            "binary_version": "3.26.0+dfsg-0ubuntu1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "opencryptoki",
        "purl": "pkg:deb/ubuntu/opencryptoki@3.26.0+dfsg-0ubuntu1?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.25.0+dfsg-0ubuntu1",
        "3.26.0+dfsg-0ubuntu1"
      ]
    }
  ],
  "aliases": [],
  "details": "openCryptoki is a PKCS#11 library and provides tooling for Linux and AIX. In versions 3.26.0 and below, the BER/DER decoding functions in the shared common library (asn1.c) accept a raw pointer but no buffer length parameter, and trust attacker-controlled BER length fields without validating them against actual buffer boundaries. All primitive decoders are affected: ber_decode_INTEGER, ber_decode_SEQUENCE, ber_decode_OCTET_STRING, ber_decode_BIT_STRING, and ber_decode_CHOICE. Additionally, ber_decode_INTEGER can produce integer underflows when the encoded length is zero. An attacker supplying a malformed BER-encoded cryptographic object through PKCS#11 operations such as C_CreateObject or C_UnwrapKey, token loading from disk, or remote backend communication can trigger out-of-bounds reads. This affects all token backends (Soft, ICA, CCA, TPM, EP11, ICSF) since the vulnerable code is in the shared common library. A patch is available thorugh commit ed378f463ef73364c89feb0fc923f4dc867332a3.",
  "id": "UBUNTU-CVE-2026-40253",
  "modified": "2026-05-20T15:27:26Z",
  "published": "2026-04-16T23:16:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-40253"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-40253"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-40253"
  ]
}



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