Vulnerability-Lookup

OESA-2026-2165 (CVE-2026-40253)

Vulnerability from osv_openeuler – Published: 2026-05-03 11:11 – Updated: 2026-08-06 11:11 – Source website

Summary

opencryptoki security update

Details

openCryptoki is an implementation of the PKCS #11 API that allows interfacing to devices that hold cryptographic information and perform cryptographic functions. openCryptoki provides application portability by isolating the application from the details of the cryptographic device. Isolating the application also provides an added level of security. The openCryptoki API provides a standard programming interface between applications and all kinds of portable cryptographic devices.

Security Fix(es):

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.(CVE-2026-40253)

Severity

6.8 (Medium)


                    
                      CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H

References

URL

Type

	https://www.openeuler.org/zh/security/security-bu…	ADVISORY
	https://nvd.nist.gov/vuln/detail/CVE-2026-40253	ADVISORY

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "aarch64": [
          "opencryptoki-3.26.0-2.oe2403.aarch64.rpm",
          "opencryptoki-debuginfo-3.26.0-2.oe2403.aarch64.rpm",
          "opencryptoki-debugsource-3.26.0-2.oe2403.aarch64.rpm",
          "opencryptoki-devel-3.26.0-2.oe2403.aarch64.rpm"
        ],
        "noarch": [
          "opencryptoki-help-3.26.0-2.oe2403.noarch.rpm"
        ],
        "src": [
          "opencryptoki-3.26.0-2.oe2403.src.rpm"
        ],
        "x86_64": [
          "opencryptoki-3.26.0-2.oe2403.x86_64.rpm",
          "opencryptoki-debuginfo-3.26.0-2.oe2403.x86_64.rpm",
          "opencryptoki-debugsource-3.26.0-2.oe2403.x86_64.rpm",
          "opencryptoki-devel-3.26.0-2.oe2403.x86_64.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:24.03-LTS",
        "name": "opencryptoki",
        "purl": "pkg:rpm/openEuler/opencryptoki\u0026distro=openEuler-24.03-LTS"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.26.0-2.oe2403"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "severity": "Medium"
  },
  "details": "openCryptoki is an implementation of the PKCS #11 API that allows interfacing to devices that hold cryptographic information and perform cryptographic functions. openCryptoki provides application portability by isolating the application from the details of the cryptographic device. Isolating the application also provides an added level of security. The openCryptoki API provides a standard programming interface between applications and all kinds of portable cryptographic devices.\r\n\r\nSecurity Fix(es):\n\nopenCryptoki 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.(CVE-2026-40253)",
  "id": "OESA-2026-2165",
  "modified": "2026-08-06T11:11:09Z",
  "published": "2026-05-03T11:11:09Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-2165"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-40253"
    }
  ],
  "schema_version": "1.7.2",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "opencryptoki security update",
  "upstream": [
    "CVE-2026-40253"
  ]
}

CVE-2026-40253 (GCVE-0-2026-40253)

Vulnerability from cvelistv5 – Published: 2026-04-16 22:04 – Updated: 2026-04-17 12:27

Title

openCryptoki: Memory safety vulnerabilities in BER/DER decoders in asn1.c

Summary

Severity

6.8 (Medium)


                        
                          CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H

SSVC

Exploitation: poc Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-04-17 12:27 UTC

CWE

CWE-125 - Out-of-bounds Read

Assigner

GitHub_M mitre root

References

2 references

URL	Tags
https://github.com/opencryptoki/opencryptoki/secu…	x_refsource_CONFIRM
https://github.com/opencryptoki/opencryptoki/comm…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
opencryptoki	opencryptoki	Affected: <= 3.26.0

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-40253",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-04-17T12:27:37.623084Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-04-17T12:27:41.682Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://github.com/opencryptoki/opencryptoki/security/advisories/GHSA-c9cf-6vr4-wfxm"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "opencryptoki",
          "vendor": "opencryptoki",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c= 3.26.0"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "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."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "LOCAL",
            "availabilityImpact": "HIGH",
            "baseScore": 6.8,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "LOW",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-125",
              "description": "CWE-125: Out-of-bounds Read",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-04-16T22:04:44.005Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/opencryptoki/opencryptoki/security/advisories/GHSA-c9cf-6vr4-wfxm",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/opencryptoki/opencryptoki/security/advisories/GHSA-c9cf-6vr4-wfxm"
        },
        {
          "name": "https://github.com/opencryptoki/opencryptoki/commit/ed378f463ef73364c89feb0fc923f4dc867332a3",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/opencryptoki/opencryptoki/commit/ed378f463ef73364c89feb0fc923f4dc867332a3"
        }
      ],
      "source": {
        "advisory": "GHSA-c9cf-6vr4-wfxm",
        "discovery": "UNKNOWN"
      },
      "title": "openCryptoki: Memory safety vulnerabilities in BER/DER decoders in asn1.c"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-40253",
    "datePublished": "2026-04-16T22:04:44.005Z",
    "dateReserved": "2026-04-10T17:31:45.786Z",
    "dateUpdated": "2026-04-17T12:27:41.682Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.