Admidio: Cross-Organization Member Data Exposure via Permission Check Mismatch in contacts_data.php

{
  "id": "9d186bea3510fd08502fc19e87bf33a59f7302cb6876af524ff9fe7d5919942d",
  "url": "https://osv.dev/vulnerability/CVE-2026-41657",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Admidio: Cross-Organization Member Data Exposure via Permission Check Mismatch in contacts_data.php",
    "summary": "Admidio is an open-source user management solution. Prior to version 5.0.9, the contacts_data.php endpoint uses a weaker permission check (isAdministratorUsers(), requiring only rol_edit_user=true) than the frontend UI (contacts.php) which correctly requires the stronger isAdministrator() (requiring rol_administrator=true) and the contacts_show_all system setting. A user manager who is not a full administrator can directly request contacts_data.php?mem_show_filter=3 to retrieve all user records across all organizations in the Admidio instance, bypassing multi-tenant organization isolation. This issue has been patched in version 5.0.9.",
    "evidence": "osv:CVE-2026-41657",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2026-41657",
      "aliases": [
        "CVE-2026-41657",
        "GHSA-g8p8-94f2-28gr"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/admidio/admidio",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "d39915697e6e0be04d02d55a46c631f53013aea6"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "5.0.9"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StringRangeExpression"
                  },
                  {
                    "range": [
                      {
                        "fixed": "d39915697e6e0be04d02d55a46c631f53013aea6"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "v5.0.9"
                  },
                  {
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "5.0.9"
                      }
                    ],
                    "source": "DESCRIPTION"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v5.0.8",
            "v5.0.7",
            "v5.0.6",
            "v5.0.5",
            "v5.0.4",
            "v34",
            "v5.0.3",
            "v5.0.2",
            "v5.0.1",
            "v5.0.0",
            "v5.0-Beta.3",
            "v5.0-Beta.2",
            "v5.0-Beta.1",
            "v4.3-Beta.1",
            "v4.1-Beta.2",
            "v4.0-Beta.1",
            "v3.2-Beta.1",
            "v3.1.5",
            "v3.0.6",
            "3.0-Beta.3",
            "3.0-Beta.1"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-41657.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:38.434155719Z",
      "provider": "osv",
      "references": [
        "https://github.com/Admidio/admidio/releases/tag/v5.0.9",
        "https://github.com/Admidio/admidio/security/advisories/GHSA-g8p8-94f2-28gr",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/41xxx/CVE-2026-41657.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-41657"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-863"
        ],
        "cna_assigner": "GitHub_M",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/41xxx/CVE-2026-41657.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-41657",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 505711,
  "published_at": "2026-05-07T02:58:09.34+00:00"
}