{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "cpe": "cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:*",
            "extracted_events": [
              {
                "introduced": "5.5.0"
              },
              {
                "fixed": "5.9.0"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "CPE_RANGE"
            ]
          },
          "events": [
            {
              "introduced": "44f81f8bc082319cebf0e37df8470aa5748c1355"
            },
            {
              "fixed": "922d04b3568c6428a9fb905ddee3ef5a68db3108"
            }
          ],
          "repo": "https://github.com/wolfssl/wolfssl",
          "type": "GIT"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "wolfSSL",
    "cwe_ids": [
      "CWE-121",
      "CWE-787"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/0xxx/CVE-2026-0819.json"
  },
  "details": "A stack buffer overflow vulnerability exists in wolfSSL's PKCS7 SignedData encoding functionality. In wc_PKCS7_BuildSignedAttributes(), when adding custom signed attributes, the code passes an incorrect capacity value (esd-\u003esignedAttribsCount) to EncodeAttributes() instead of the remaining available space in the fixed-size signedAttribs[7] array. When an application sets pkcs7-\u003esignedAttribsSz to a value greater than MAX_SIGNED_ATTRIBS_SZ (default 7) minus the number of default attributes already added, EncodeAttributes() writes beyond the array bounds, causing stack memory corruption. In WOLFSSL_SMALL_STACK builds, this becomes heap corruption. Exploitation requires an application that allows untrusted input to control the signedAttribs array size when calling wc_PKCS7_EncodeSignedData() or related signing functions.",
  "id": "CVE-2026-0819",
  "modified": "2026-07-16T03:31:08.969473813Z",
  "published": "2026-03-19T16:54:33.442Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/0xxx/CVE-2026-0819.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-0819"
    },
    {
      "type": "FIX",
      "url": "https://github.com/wolfSSL/wolfssl/pull/9630"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/wolfSSL/wolfssl"
    }
  ],
  "schema_version": "1.8.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N/E:U",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Stack buffer overflow in PKCS7 SignedData encoding with custom signed attributes"
}