{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "2.7.0"
              }
            ],
            "source": [
              "DESCRIPTION",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4007498b13582d90ee1eda5d9920c324428b98b3"
            },
            {
              "fixed": "1b8fad04df4953230c9951c57678ee45c8aead85"
            }
          ],
          "repo": "https://github.com/bcgit/bc-csharp",
          "type": "GIT"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "bcorg",
    "cwe_ids": [
      "CWE-835"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63570.json"
  },
  "details": "Loop with unreachable exit condition in Pkcs12Store.GetCertificateChain in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows an attacker who can supply a crafted PKCS#12 file to an application that loads it and requests a key entry's certificate chain to cause a denial of service, in which the call never returns and consumes CPU and memory until an OutOfMemoryException, via certificates whose issuer links form a cycle, for example two certificates whose AuthorityKeyIdentifier extensions each identify the other's public key. This happens because the chain-building loop stops only when no issuer is found or a certificate links to itself, and keeps no record of certificates already visited. The key-identifier links are followed without checking signatures.",
  "id": "CVE-2026-63570",
  "modified": "2026-10-04T02:30:36.405593462Z",
  "published": "2026-10-02T07:01:18.029Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://www.nuget.org/packages/BouncyCastle.Cryptography"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63570.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/bcgit/bc-csharp/wiki/CVE-2026-63570"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-63570"
    },
    {
      "type": "FIX",
      "url": "https://github.com/bcgit/bc-csharp/commit/1b8fad04df4953230c9951c57678ee45c8aead85"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/bcgit/bc-csharp"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Pkcs12Store.GetCertificateChain loops forever on cyclic issuer links"
}