Phar Deserialization leading to Arbitrary File Deletion in my little forum

{
  "id": "e1d5d5e4d8b58ff1e75075f3e78e5a27369893b89cae04b0848ead0feb4256a1",
  "url": "https://osv.dev/vulnerability/CVE-2026-25923",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Phar Deserialization leading to Arbitrary File Deletion in my little forum",
    "summary": "my little forum is a PHP and MySQL based internet forum that displays the messages in classical threaded view. Prior to 20260208.1, the application fails to filter the phar:// protocol in URL validation, allowing attackers to upload a malicious Phar Polyglot file (disguised as JPEG) via the image upload feature, trigger Phar deserialization through BBCode [img] tag processing, and exploit Smarty 4.1.0 POP chain to achieve arbitrary file deletion. This vulnerability is fixed in 20260208.1.",
    "evidence": "osv:CVE-2026-25923",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-25923",
      "aliases": [
        "CVE-2026-25923",
        "GHSA-wr9p-3c3g-78fw"
      ],
      "metrics": [
        {
          "type": "CVSS_V4",
          "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/my-little-forum/mylittleforum",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "a8fc667ece9301506a739fd62dc2b444e8485a22"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "20260208.1"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StringRangeExpression"
                  },
                  {
                    "range": [
                      {
                        "fixed": "a8fc667ece9301506a739fd62dc2b444e8485a22"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "20260208.1"
                  },
                  {
                    "cpe": "cpe:2.3:a:mylittleforum:my_little_forum:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "20260208.1"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "20251129.1",
            "20251021.1",
            "20251010.1",
            "20250921.1",
            "20250422.1",
            "20250323.1",
            "20241215.1",
            "20240827.1",
            "20240729.1",
            "20220803.1",
            "20220529.1",
            "20220517.1",
            "20220509.1",
            "20220508.1",
            "2.4.99.3",
            "2.4.99.1",
            "2.4.8",
            "2.4.7",
            "2.4.6",
            "2.4.5",
            "2.4.4",
            "2.4.3",
            "2.4.2",
            "2.4.1",
            "v2.4",
            "2.4",
            "v2.3.99.3",
            "2.3.99.3",
            "v2.3.99.2",
            "v2.3.7",
            "v2.3.7beta2",
            "v2.3.7beta",
            "v2.3.6.1",
            "v2.3.6",
            "v2.3.5",
            "v2.3.4",
            "v2.3.3",
            "v2.3.2",
            "v2.3",
            "v2.2.8",
            "v2.2.7",
            "v2.2.6",
            "v2.2.5",
            "v2.2.4",
            "v2.2.3",
            "v2.2.2",
            "v2.2.1",
            "v2.2"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-25923.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:21.821960734Z",
      "provider": "osv",
      "references": [
        "https://github.com/My-Little-Forum/mylittleforum/releases/tag/20260208.1",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/25xxx/CVE-2026-25923.json",
        "https://github.com/My-Little-Forum/mylittleforum/security/advisories/GHSA-wr9p-3c3g-78fw",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-25923"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-434",
          "CWE-502"
        ],
        "cna_assigner": "GitHub_M",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/25xxx/CVE-2026-25923.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-25923",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 488270,
  "published_at": "2026-02-09T21:56:02.862+00:00"
}