{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "4.0.0"
              },
              {
                "fixed": "4.0.2"
              },
              {
                "introduced": "3.6.0"
              },
              {
                "fixed": "3.6.4"
              },
              {
                "introduced": "3.5.0"
              },
              {
                "fixed": "3.5.8"
              },
              {
                "introduced": "3.4.0"
              },
              {
                "fixed": "3.4.7"
              },
              {
                "introduced": "3.0.0"
              },
              {
                "fixed": "3.0.22"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "11b7b6ea3b65a584e1d31408ed1bdb139465cffd"
            },
            {
              "introduced": "7b371d80d959ec9ab4139d09d78e83c090de9779"
            },
            {
              "introduced": "636dfadc70ce26f2473870570bfd9ec352806b1d"
            },
            {
              "introduced": "98acb6b02839c609ef5b837794e08d906d965335"
            },
            {
              "introduced": "89cd17a031e022211684eb7eb41190cf1910f9fa"
            },
            {
              "fixed": "f089acdf4bc7ba94a79f4bf6eb7362c3e7d14aa9"
            },
            {
              "fixed": "d3c1b1169b3569ff3069e5b399f47b2b28e03d79"
            },
            {
              "fixed": "f4dc4d58b48d346a8270183f89acf826d459b0ca"
            },
            {
              "fixed": "0c5d912057abf47505b4ad455da49fbab99b76f1"
            },
            {
              "fixed": "a279090b9cd6b682a5a178410765a63e619fa2d9"
            },
            {
              "fixed": "37882aa2e0256e1072442a8f62f7db45b995c45b"
            },
            {
              "fixed": "a17cc8d612ecff6d94a9b7ca8b5283ddf5ff570e"
            },
            {
              "fixed": "a1f348ccb328c3afbd4ba6883f9b7c813c043259"
            }
          ],
          "repo": "https://github.com/openssl/openssl",
          "type": "GIT"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "openssl",
    "cwe_ids": [
      "CWE-476"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63076.json"
  },
  "details": "Issue summary: OpenSSL CMP password based protection verification only\nchecks whether the protectionAlg parameter was not NULL and not its\nASN.1 type, before treating it as a PBMParameter. A crafted message can\ncontain a parameter of a different type, which is then dereferenced as an\ninvalid pointer.\n\nImpact summary: A remote, unauthenticated attacker can crash an application\nacting as a CMP server that accepts PBM-protected messages, or a CMP client\ntalking to a malicious or intercepted CMP server, resulting in a Denial of\nService.\n\nCWE: CWE-476: NULL Pointer Dereference\n\nDescription: When verifying the password-based MAC protection of a CMP\nmessage, OpenSSL library reads the protectionAlg algorithm parameter with\nX509_ALGOR_get0(), which returns both the parameter type and its value\npointer. The value is then cast to an ASN1_STRING and treated as the\nexpected PBMParameter after only checking that pointer is not NULL. The\nparameter type returned by X509_ALGOR_get0() was never consulted.\n\nThis happens during protection verification, before any MAC is computed, so\nno knowledge of the PBM shared secret is required; the only precondition is\nthat PBM verification is reachable. On the server side this is reached from\nOSSL_CMP_SRV_process_request() for any application that stands up a CMP\nserver accepting PBM-protected messages, and on the client side from CMP\nresponse validation against a malicious or on-path (MITM) server. The\nreliable consequence is a denial of service; there is no memory disclosure,\nno controlled memory write, and no path to code execution. CMP is a\nspecialized feature that an application must explicitly enable.\n\nFIPS impact: no\nAs the CMP code lives outside the FIPS module boundary, no FIPS modules\nare affected by this CVE.",
  "id": "CVE-2026-63076",
  "modified": "2026-08-30T03:31:04.354674781Z",
  "published": "2026-08-25T13:00:11.218Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63076.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-63076"
    },
    {
      "type": "ADVISORY",
      "url": "https://openssl-library.org/news/secadv/20260825.txt"
    },
    {
      "type": "FIX",
      "url": "https://github.com/openssl/openssl/commit/37882aa2e0256e1072442a8f62f7db45b995c45b"
    },
    {
      "type": "FIX",
      "url": "https://github.com/openssl/openssl/commit/a17cc8d612ecff6d94a9b7ca8b5283ddf5ff570e"
    },
    {
      "type": "FIX",
      "url": "https://github.com/openssl/openssl/commit/a1f348ccb328c3afbd4ba6883f9b7c813c043259"
    },
    {
      "type": "FIX",
      "url": "https://github.com/openssl/openssl/commit/a7af46a92d0ce19a90e669ef56d2576a07924226"
    },
    {
      "type": "FIX",
      "url": "https://github.com/openssl/openssl/commit/cdacfff557389abfa9e4615abded2ec984517d6c"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Invalid Pointer Dereference in CMP Server via Crafted protectionAlg"
}