Starman versions before 0.4019 for Perl send response bodies for HEAD requests, desynchronizing responses on keep-alive connections

{
  "id": "4352053056d1865a12b98d26ed0914a05fb205669ac43398b9e7a076a6048ef4",
  "url": "https://www.cve.org/CVERecord?id=CVE-2026-115823",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Starman versions before 0.4019 for Perl send response bodies for HEAD requests, desynchronizing responses on keep-alive connections",
    "summary": "Starman versions before 0.4019 for Perl send response bodies for HEAD requests, desynchronizing responses on keep-alive connections. For a HEAD request Starman omits chunked framing but still writes the body returned by the application, on both the array and streaming response paths. Responses with a 1xx, 204 or 304 status also carry the body. On a keep-alive or pipelined connection the client reads those bytes as the start of the next response. A front-end proxy that reuses upstream connections may then pair responses with the wrong requests.",
    "evidence": "cve:CVE-2026-115823",
    "products": [],
    "severity": "unknown",
    "structured": {
      "id": "CVE-2026-115823",
      "aliases": [
        "CVE-2026-115823"
      ],
      "metrics": [],
      "affected": [
        {
          "repo": "https://github.com/miyagawa/Starman",
          "modules": [
            "Starman"
          ],
          "versions": [
            {
              "status": "affected",
              "version": "0",
              "lessThan": "0.4019",
              "versionType": "custom"
            }
          ],
          "packageURL": "pkg:cpan/Starman",
          "packageName": "Starman",
          "programFiles": [
            "lib/Starman/Server.pm"
          ],
          "collectionURL": "https://cpan.org/modules",
          "defaultStatus": "unaffected",
          "programRoutines": [
            {
              "name": "Starman::Server::_finalize_response"
            }
          ]
        }
      ],
      "modified": "2026-10-25T16:51:19.961Z",
      "provider": "cve",
      "references": [
        "https://github.com/miyagawa/Starman/commit/91c47c529cd1e100f938486896ea9083ec3ec7bf.patch",
        "https://metacpan.org/release/MIYAGAWA/Starman-0.4019/changes"
      ],
      "provider_metadata": {
        "cna": {
          "orgId": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
          "shortName": "CPANSec",
          "dateUpdated": "2026-10-25T16:51:19.961Z"
        }
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-115823",
        "evidence": "/cveMetadata/cveId"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-cve",
  "document_id": 172000,
  "published_at": "2026-10-25T16:51:19.961+00:00"
}