wolfSSL_PKCS7_verify() reports success for degenerate (certs-only) PKCS#7 with no signer

{
  "id": "1b97d4c3e364c38a6198ccc9b17c6d8654f10d8a23cc8eb20d54753f3b062b86",
  "url": "https://osv.dev/vulnerability/CVE-2026-55961",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "wolfSSL_PKCS7_verify() reports success for degenerate (certs-only) PKCS#7 with no signer",
    "summary": "wolfSSL_PKCS7_verify() returning success for a degenerate (certs-only) PKCS#7 object that contains no signer. Such an object has empty signerInfos, so the underlying signed-data verification succeeds without authenticating any content. The compatibility-layer verify path now rejects the object when no signer signature has actually been verified, so a PKCS#7 carrying no valid signature is no longer reported as verified. This is enforced regardless of the PKCS7_NOVERIFY flag, which only suppresses signer certificate chain validation and was never intended to waive the requirement that a signature exist. Only affects OpenSSL compatibility builds that call the PKCS7_verify() compatibility API on potentially degenerate PKCS#7 bundles.",
    "evidence": "osv:CVE-2026-55961",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-55961",
      "aliases": [
        "CVE-2026-55961"
      ],
      "metrics": [
        {
          "type": "CVSS_V4",
          "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/wolfssl/wolfssl",
              "type": "GIT",
              "events": [
                {
                  "introduced": "a7350b7d2ed15648443253cb39ad9195df184139"
                },
                {
                  "fixed": "ac01707f552c611fbd135cc723b2682b3e7f80f2"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "3.15.7"
                      },
                      {
                        "last_affected": "5.9.1"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StandardRange"
                  },
                  {
                    "cpe": "cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "3.15.7"
                      },
                      {
                        "fixed": "5.9.2"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v5.9.1-stable",
            "v5.9.0-stable",
            "v5.8.4-stable",
            "wolfEntropy2d",
            "v5.8.2-stable",
            "wolfEntropy1",
            "v5.8.0-stable",
            "v5.7.6-stable",
            "v5.7.4-stable",
            "v5.2.1",
            "v5.7.2-stable",
            "v5.7.0-stable",
            "v5.6.6-stable",
            "v5.6.4-stable",
            "WCv5.0-RC12",
            "WCv5.0-RC11",
            "WCv5.0-RC10",
            "v5.6.2-stable",
            "v5.6.3-stable",
            "v5.6.0-stable",
            "v5.5.4-stable",
            "v5.5.3-stable",
            "v5.5.2-stable",
            "v5.5.1-stable",
            "v5.5.0-stable",
            "v5.4.0-stable",
            "v5.3.0-stable",
            "v5.2.0-stable",
            "v5.1.0-stable",
            "v5.0.0-stable",
            "WCv5.0-RC9",
            "v4.8.0-stable",
            "v4.7.1r",
            "v4.7.0-stable",
            "v4.6.0-stable",
            "v4.5.0-stable",
            "v4.4.0-stable",
            "v4.3.0-stable",
            "v4.2.0c",
            "v4.2.0-stable",
            "v4.1.0-stable",
            "v4.0.0-stable",
            "list",
            "v3.15.7-stable"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-55961.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:42.428801983Z",
      "provider": "osv",
      "references": [
        "https://www.wolfssl.com/docs/security-vulnerabilities/",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/55xxx/CVE-2026-55961.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-55961",
        "https://github.com/wolfSSL/wolfssl/pull/10702",
        "https://github.com/wolfSSL/wolfssl"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-347"
        ],
        "cna_assigner": "wolfSSL",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/55xxx/CVE-2026-55961.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-55961",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 509982,
  "published_at": "2026-06-25T16:51:18.157+00:00"
}