Phar TAR phar_tar_number() Integer Overflow - Archive Entry Injection

{
  "id": "7a1103c1ab6ea845b21fcf61aff84b6f6e269a44d1e40d20cc199d265c656254",
  "url": "https://osv.dev/vulnerability/BIT-php-2026-6103",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Phar TAR phar_tar_number() Integer Overflow - Archive Entry Injection",
    "summary": "phar_tar_number() parses the octal size field of a TAR header into a uint32_t with no overflow check. The field is 11 octal digits wide and holds values up to 0x1FFFFFFFF, so a size above 0xFFFFFFFF silently wraps. The parser then skips the wrong number of data blocks and interprets attacker-controlled file content as the next TAR header, which lets a crafted archive inject entries that PharData reports and extracts as if they were genuine.",
    "evidence": "osv:BIT-php-2026-6103",
    "products": [
      {
        "name": {
          "value": "php",
          "evidence": "/affected/0/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "8.2.34",
            "evidence": "/affected/0/ranges"
          },
          {
            "value": "8.3.35",
            "evidence": "/affected/0/ranges"
          },
          {
            "value": "8.4.26",
            "evidence": "/affected/0/ranges"
          },
          {
            "value": "8.5.11",
            "evidence": "/affected/0/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "medium",
    "structured": {
      "id": "BIT-php-2026-6103",
      "aliases": [
        "BIT-libphp-2026-6103",
        "BIT-php-2026-6103",
        "BIT-php-min-2026-6103",
        "CVE-2026-6103",
        "GHSA-j3wh-g957-2m85"
      ],
      "affected": [
        {
          "ranges": [
            {
              "type": "SEMVER",
              "events": [
                {
                  "introduced": "8.2.0"
                },
                {
                  "fixed": "8.2.34"
                },
                {
                  "introduced": "8.3.0"
                },
                {
                  "fixed": "8.3.35"
                },
                {
                  "introduced": "8.4.0"
                },
                {
                  "fixed": "8.4.26"
                },
                {
                  "introduced": "8.5.0"
                },
                {
                  "fixed": "8.5.11"
                }
              ]
            }
          ],
          "package": {
            "name": "php",
            "purl": "pkg:bitnami/php",
            "ecosystem": "Bitnami"
          },
          "severity": [
            {
              "type": "CVSS_V3",
              "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N"
            }
          ],
          "database_specific": {
            "source": "https://github.com/bitnami/vulndb/tree/main/data/php/BIT-php-2026-6103.json"
          }
        }
      ],
      "modified": "2026-10-26T08:45:05.550068420Z",
      "provider": "osv",
      "references": [
        "https://github.com/php/php-src/security/advisories/GHSA-j3wh-g957-2m85",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-6103"
      ],
      "provider_metadata": {
        "cpes": [
          "cpe:2.3:a:php:php:*:*:*:*:*:*:*:*"
        ],
        "severity": "Medium"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-6103",
        "evidence": "/aliases"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/database_specific/severity"
  },
  "source_id": "core-osv",
  "document_id": 446800,
  "published_at": "2026-10-01T09:33:52.29+00:00"
}