Tnef: heap out-of-bounds read in get_rtf_data_from_buf() via uncompressed rtf mapi value

{
  "id": "546e86c90ba30cc66872660626aee2187003a79a344d46f571bc50177b8fac8a",
  "url": "https://osv.dev/vulnerability/CVE-2026-103678",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Tnef: heap out-of-bounds read in get_rtf_data_from_buf() via uncompressed rtf mapi value",
    "summary": "A flaw was found in tnef. An attacker can exploit this vulnerability by providing a specially crafted file containing uncompressed Rich Text Format (RTF) data. Because the application fails to properly validate input buffer boundaries before copying data in get_rtf_data_from_buf(), reading beyond the allocated memory occurs. This flaw can cause the application to crash, leading to a Denial of Service (DoS), or leak sensitive memory contents into extracted output files.",
    "evidence": "osv:CVE-2026-103678",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2026-103678",
      "aliases": [
        "CVE-2026-103678"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:L"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/verdammelt/tnef",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "last_affected": "8edd0e046736764c6decc8cd6e0e739438408f3e"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "last_affected": "1.4.18"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StandardRange"
                  },
                  {
                    "cpe": "cpe:2.3:a:tnef_project:tnef:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "last_affected": "1.4.18"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "1.4.18",
            "1.4.17",
            "1.4.16",
            "1.4.15",
            "1.4.14",
            "1.4.12",
            "TNEF-1.4.11",
            "1.4.11",
            "TNEF-1.4.10",
            "1.4.10"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-103678.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:51.591438632Z",
      "provider": "osv",
      "references": [
        "https://access.redhat.com/security/cve/CVE-2026-103678",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/103xxx/CVE-2026-103678.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-103678",
        "https://bugzilla.redhat.com/show_bug.cgi?id=2544476",
        "https://github.com/verdammelt/tnef"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-125"
        ],
        "cna_assigner": "fedora",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/103xxx/CVE-2026-103678.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-103678",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 520275,
  "published_at": "2026-10-01T11:34:48.652+00:00"
}