ocaml-mirage-crypto — security advisory

{
  "id": "c4abec47b9ec285a5ac3d98e7abded107e82796c79d638e3f36e364b1088a3a1",
  "url": "https://osv.dev/vulnerability/UBUNTU-CVE-2026-87733",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "UBUNTU-CVE-2026-87733",
    "summary": "An issue was discovered in the mirage-crypto-ec function before 2.2.0 for OCaml. The ECDSA functions {P256,P384,P521}.Dsa.pub_of_octets accept 0x00, the encoding of the point at infinity, as a public key. With that public key, signatures can be forged without a private key.",
    "evidence": "osv:UBUNTU-CVE-2026-87733",
    "products": [
      {
        "name": {
          "value": "ocaml-mirage-crypto",
          "evidence": "/affected/0/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [],
        "affected_versions": [
          {
            "value": "0.10.5-4",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "0.10.5-4build2",
            "evidence": "/affected/0/versions"
          }
        ]
      },
      {
        "name": {
          "value": "ocaml-mirage-crypto",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [],
        "affected_versions": [
          {
            "value": "0.11.1-3",
            "evidence": "/affected/1/versions"
          },
          {
            "value": "0.11.2-1",
            "evidence": "/affected/1/versions"
          },
          {
            "value": "0.11.2-1build1",
            "evidence": "/affected/1/versions"
          },
          {
            "value": "0.11.2-2build3",
            "evidence": "/affected/1/versions"
          }
        ]
      },
      {
        "name": {
          "value": "ocaml-mirage-crypto",
          "evidence": "/affected/2/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [],
        "affected_versions": [
          {
            "value": "2.0.2-1build5",
            "evidence": "/affected/2/versions"
          },
          {
            "value": "2.4.0-1",
            "evidence": "/affected/2/versions"
          }
        ]
      },
      {
        "name": {
          "value": "ocaml-mirage-crypto",
          "evidence": "/affected/3/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [],
        "affected_versions": [
          {
            "value": "2.0.1-1build1",
            "evidence": "/affected/3/versions"
          },
          {
            "value": "2.0.2-1build1",
            "evidence": "/affected/3/versions"
          },
          {
            "value": "2.0.2-1build2",
            "evidence": "/affected/3/versions"
          },
          {
            "value": "2.0.2-1build3",
            "evidence": "/affected/3/versions"
          },
          {
            "value": "2.0.2-1build5",
            "evidence": "/affected/3/versions"
          }
        ]
      }
    ],
    "severity": "medium",
    "structured": {
      "id": "UBUNTU-CVE-2026-87733",
      "aliases": [
        "UBUNTU-CVE-2026-87733"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N"
        },
        {
          "type": "Ubuntu",
          "score": "medium"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "0"
                }
              ]
            }
          ],
          "package": {
            "name": "ocaml-mirage-crypto",
            "purl": "pkg:deb/ubuntu/ocaml-mirage-crypto?arch=source&distro=jammy",
            "ecosystem": "Ubuntu:22.04:LTS"
          },
          "versions": [
            "0.10.5-4",
            "0.10.5-4build2"
          ],
          "database_specific": {
            "source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-87733.json"
          },
          "ecosystem_specific": {
            "binaries": [
              {
                "binary_name": "libmirage-crypto-ocaml",
                "binary_version": "0.10.5-4build2"
              }
            ]
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "0"
                }
              ]
            }
          ],
          "package": {
            "name": "ocaml-mirage-crypto",
            "purl": "pkg:deb/ubuntu/ocaml-mirage-crypto?arch=source&distro=noble",
            "ecosystem": "Ubuntu:24.04:LTS"
          },
          "versions": [
            "0.11.1-3",
            "0.11.2-1",
            "0.11.2-1build1",
            "0.11.2-2build3"
          ],
          "database_specific": {
            "source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-87733.json"
          },
          "ecosystem_specific": {
            "binaries": [
              {
                "binary_name": "libmirage-crypto-ocaml",
                "binary_version": "0.11.2-2build3"
              }
            ]
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "0"
                }
              ]
            }
          ],
          "package": {
            "name": "ocaml-mirage-crypto",
            "purl": "pkg:deb/ubuntu/ocaml-mirage-crypto?arch=source&distro=stonking",
            "ecosystem": "Ubuntu:26.10"
          },
          "versions": [
            "2.0.2-1build5",
            "2.4.0-1"
          ],
          "database_specific": {
            "source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-87733.json"
          },
          "ecosystem_specific": {
            "binaries": [
              {
                "binary_name": "libmirage-crypto-ocaml",
                "binary_version": "2.4.0-1"
              }
            ]
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "0"
                }
              ]
            }
          ],
          "package": {
            "name": "ocaml-mirage-crypto",
            "purl": "pkg:deb/ubuntu/ocaml-mirage-crypto?arch=source&distro=resolute",
            "ecosystem": "Ubuntu:26.04:LTS"
          },
          "versions": [
            "2.0.1-1build1",
            "2.0.2-1build1",
            "2.0.2-1build2",
            "2.0.2-1build3",
            "2.0.2-1build5"
          ],
          "database_specific": {
            "source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-87733.json"
          },
          "ecosystem_specific": {
            "binaries": [
              {
                "binary_name": "libmirage-crypto-ocaml",
                "binary_version": "2.0.2-1build5"
              }
            ]
          }
        }
      ],
      "modified": "2026-10-17T13:01:14.812120951Z",
      "provider": "osv",
      "upstream": [
        "CVE-2026-87733"
      ],
      "references": [
        "https://ubuntu.com/security/CVE-2026-87733",
        "https://www.cve.org/CVERecord?id=CVE-2026-87733",
        "https://osv.dev/vulnerability/OSEC-2026-13"
      ]
    },
    "related_cves": [
      {
        "value": "CVE-2026-87733",
        "evidence": "/upstream"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 361352,
  "published_at": "2026-09-09T05:18:00+00:00"
}