Stack Buffer Overflow in rxi/microtar raw_to_header() via non-null-terminated TAR name field

{
  "id": "20dc2d6647df1014548073ab0e8ad8bd400307c0a8a9480f25b381bbe5821841",
  "url": "https://osv.dev/vulnerability/CVE-2026-55738",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Stack Buffer Overflow in rxi/microtar raw_to_header() via non-null-terminated TAR name field",
    "summary": "A stack-based buffer overflow exists in the raw_to_header function in src/microtar.c in rxi microtar 0.1.0. The function copies the 100-byte name and linkname fields of a TAR header with strcpy without guaranteeing null termination of the source.",
    "evidence": "osv:CVE-2026-55738",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-55738",
      "aliases": [
        "CVE-2026-55738"
      ],
      "metrics": [
        {
          "type": "CVSS_V4",
          "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/rxi/microtar",
              "type": "GIT",
              "events": [
                {
                  "introduced": "956791770defa4d06696b30db276e88a09ad3538"
                },
                {
                  "last_affected": "956791770defa4d06696b30db276e88a09ad3538"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "0.1.0"
                      },
                      {
                        "last_affected": "0.1.0"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StandaloneSingleVersion"
                  }
                ]
              }
            }
          ],
          "versions": [
            "0.1.0",
            "v0.1.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-55738.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:35.811371579Z",
      "provider": "osv",
      "references": [
        "https://github.com/rxi/microtar/blob/master/src/microtar.c#L111",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/55xxx/CVE-2026-55738.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-55738",
        "https://github.com/rxi/microtar",
        "https://raw.githubusercontent.com/rxi/microtar/master/src/microtar.c"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-121",
          "CWE-170"
        ],
        "cna_assigner": "TuranSec",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/55xxx/CVE-2026-55738.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-55738",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 503378,
  "published_at": "2026-06-17T13:45:00.399+00:00"
}