Vulnerability-Lookup

CVE-2026-41657 (GCVE-0-2026-41657)

Vulnerability from cvelistv5 – Published: 2026-05-07 02:58 – Updated: 2026-05-07 12:44

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.

Severity

4.9 (Medium)


                        
                          CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-05-07 12:44 UTC

CWE

CWE-863 - Incorrect Authorization

Assigner

GitHub_M mitre root Scorecard

References

2 references

URL	Tags
https://github.com/Admidio/admidio/security/advis…	x_refsource_CONFIRM
https://github.com/Admidio/admidio/releases/tag/v5.0.9	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version	CPE status
Admidio	admidio	Affected: < 5.0.9	guessed

Show details on NVD website

JSON

To clipboard

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FKIE_CVE-2026-41657

Vulnerability from fkie_nvd - Published: 2026-05-07 04:16 - Updated: 2026-06-17 10:46

Severity

4.9 (Medium) - CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N

Summary

References

	URL	Tags
	security-advisories@github.com	https://github.com/Admidio/admidio/releases/tag/v5.0.9
	security-advisories@github.com	https://github.com/Admidio/admidio/security/advisories/GHSA-g8p8-94f2-28gr
	134c704f-9b21-4f2e-91b3-4a467353bcc0	https://github.com/Admidio/admidio/security/advisories/GHSA-g8p8-94f2-28gr

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "admidio",
          "vendor": "Admidio",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 5.0.9"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "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."
    }
  ],
  "id": "CVE-2026-41657",
  "lastModified": "2026-06-17T10:46:57.263",
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          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 4.9,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "NONE",
          "privilegesRequired": "HIGH",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N",
          "version": "3.1"
        },
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        "impactScore": 3.6,
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        "type": "Secondary"
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}

GHSA-G8P8-94F2-28GR

Vulnerability from github – Published: 2026-04-29 21:44 – Updated: 2026-05-08 19:55

Summary

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

Details

Summary

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.

Details

The frontend page contacts.php and the backend data endpoint contacts_data.php have mismatched authorization checks for the "show all organizations" filter (mem_show_filter=3).

Frontend guard at modules/contacts/contacts.php:80:

if ($gCurrentUser->isAdministrator() && $gSettingsManager->getBool('contacts_show_all')) {
    // Only then is filter=3 ("All Organizations") shown in the dropdown
    $selectBoxValues = array(
        ...
        '3' => array('3', $gL10n->get('SYS_ALL_CONTACTS'), $gL10n->get('SYS_ALL_ORGANIZATIONS'))
    );
}

This correctly requires both isAdministrator() (rol_administrator=true) AND the contacts_show_all setting.

Backend check at modules/contacts/contacts_data.php:235:

} elseif (($getMembersShowFilter === 3) && $gCurrentUser->isAdministratorUsers()) {
    $mainSql = $contactsListConfig->getSql(
        array(
            'showAllMembersDatabase' => true,
            ...
        )
    );

This only requires isAdministratorUsers() which checks rol_edit_user=true — a weaker permission available to non-admin "user manager" roles. The contacts_show_all setting is never checked.

The critical difference between the two methods (from src/Users/Entity/User.php): - isAdministrator() (line 1507): checks the rol_administrator flag — full system administrator - isAdministratorUsers() (line 1625): checks rol_edit_user right — user management module access only

When showAllMembersDatabase=true reaches ListConfiguration::getSql() (at src/Roles/Entity/ListConfiguration.php:1022-1028), the generated SQL removes ALL organization filtering:

} elseif ($optionsAll['showAllMembersDatabase']) {
    $sql = 'SELECT DISTINCT ' . $sqlMemLeader . $sqlIdColumns . $sqlColumnNames . '
              FROM ' . TBL_USERS . '
                   ' . $sqlJoin . '
             WHERE usr_valid = true ' .
        $sqlWhere .
        $sqlOrderBys;
}

Compare with the default query which includes cat_org_id = $gCurrentOrgId to restrict results to the current organization.

The cross-org indicator subqueries at line 169 do correctly check isAdministrator(), so the member_other_orga columns return 0 — but this only affects display indicators, not the actual user data returned.

PoC

Prerequisites: An Admidio instance with at least two organizations sharing the same database. A user account in Organization A assigned to a role with rol_edit_user=1 but rol_administrator=0.

Step 1: Log in as the user manager account and capture the session cookie.

Step 2: Request all users across all organizations by directly calling the data endpoint:

curl -s -b 'PHPSESSID=<user_manager_session>' \
  'https://target/adm_program/modules/contacts/contacts_data.php?mem_show_filter=3&draw=1&start=0&length=100&search%5Bvalue%5D='

Expected behavior: The request should be rejected or return only current-organization users, since the user is not a full administrator and the frontend never offers filter=3 to non-administrators.

Actual behavior: The endpoint returns a JSON response containing all users from ALL organizations in the database, including: - User UUIDs (usr_uuid) - Login names (login_name) - Email addresses (member_email) - All configured profile fields (names, addresses, phone numbers, etc.)

Step 3: Verify that users from Organization B (where the attacker has no membership) appear in the results by checking the member_this_orga field — it will be 0 for cross-org users.

Impact

In multi-organization Admidio deployments (the primary use case for organization isolation), a user manager in one organization can exfiltrate the complete member directory of all other organizations sharing the same database. Exposed data includes:

Full names and all configured profile fields
Email addresses
Login names (useful for credential attacks)
User UUIDs (useful for targeting other API endpoints)

This completely bypasses the multi-tenant organization isolation boundary. The contacts_show_all admin setting (intended to control this feature) is also bypassed, meaning even instances where administrators have explicitly disabled cross-org viewing are affected.

Recommended Fix

Change line 235 in modules/contacts/contacts_data.php to match the frontend guard at contacts.php:80:

// Before (vulnerable):
} elseif (($getMembersShowFilter === 3) && $gCurrentUser->isAdministratorUsers()) {

// After (fixed):
} elseif (($getMembersShowFilter === 3) && $gCurrentUser->isAdministrator() && $gSettingsManager->getBool('contacts_show_all')) {

Additionally, as defense-in-depth, add an early rejection at the top of the file (after line 59) to block the filter value entirely for unauthorized users:

if ($getMembersShowFilter === 3 && (!$gCurrentUser->isAdministrator() || !$gSettingsManager->getBool('contacts_show_all'))) {
    $getMembersShowFilter = 0; // Fall back to default
}

Severity

4.9 (Medium)


                  
                    CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N

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{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 5.0.8"
      },
      "package": {
        "ecosystem": "Packagist",
        "name": "admidio/admidio"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "5.0.9"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-41657"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-863"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-04-29T21:44:24Z",
    "nvd_published_at": "2026-05-07T04:16:28Z",
    "severity": "MODERATE"
  },
  "details": "## Summary\n\nThe `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.\n\n## Details\n\nThe frontend page `contacts.php` and the backend data endpoint `contacts_data.php` have mismatched authorization checks for the \"show all organizations\" filter (`mem_show_filter=3`).\n\n**Frontend guard** at `modules/contacts/contacts.php:80`:\n```php\nif ($gCurrentUser-\u003eisAdministrator() \u0026\u0026 $gSettingsManager-\u003egetBool(\u0027contacts_show_all\u0027)) {\n    // Only then is filter=3 (\"All Organizations\") shown in the dropdown\n    $selectBoxValues = array(\n        ...\n        \u00273\u0027 =\u003e array(\u00273\u0027, $gL10n-\u003eget(\u0027SYS_ALL_CONTACTS\u0027), $gL10n-\u003eget(\u0027SYS_ALL_ORGANIZATIONS\u0027))\n    );\n}\n```\nThis correctly requires both `isAdministrator()` (`rol_administrator=true`) AND the `contacts_show_all` setting.\n\n**Backend check** at `modules/contacts/contacts_data.php:235`:\n```php\n} elseif (($getMembersShowFilter === 3) \u0026\u0026 $gCurrentUser-\u003eisAdministratorUsers()) {\n    $mainSql = $contactsListConfig-\u003egetSql(\n        array(\n            \u0027showAllMembersDatabase\u0027 =\u003e true,\n            ...\n        )\n    );\n```\nThis only requires `isAdministratorUsers()` which checks `rol_edit_user=true` \u2014 a weaker permission available to non-admin \"user manager\" roles. The `contacts_show_all` setting is never checked.\n\n**The critical difference between the two methods** (from `src/Users/Entity/User.php`):\n- `isAdministrator()` (line 1507): checks the `rol_administrator` flag \u2014 full system administrator\n- `isAdministratorUsers()` (line 1625): checks `rol_edit_user` right \u2014 user management module access only\n\nWhen `showAllMembersDatabase=true` reaches `ListConfiguration::getSql()` (at `src/Roles/Entity/ListConfiguration.php:1022-1028`), the generated SQL removes ALL organization filtering:\n```php\n} elseif ($optionsAll[\u0027showAllMembersDatabase\u0027]) {\n    $sql = \u0027SELECT DISTINCT \u0027 . $sqlMemLeader . $sqlIdColumns . $sqlColumnNames . \u0027\n              FROM \u0027 . TBL_USERS . \u0027\n                   \u0027 . $sqlJoin . \u0027\n             WHERE usr_valid = true \u0027 .\n        $sqlWhere .\n        $sqlOrderBys;\n}\n```\n\nCompare with the default query which includes `cat_org_id = $gCurrentOrgId` to restrict results to the current organization.\n\nThe cross-org indicator subqueries at line 169 do correctly check `isAdministrator()`, so the `member_other_orga` columns return 0 \u2014 but this only affects display indicators, not the actual user data returned.\n\n## PoC\n\n**Prerequisites:** An Admidio instance with at least two organizations sharing the same database. A user account in Organization A assigned to a role with `rol_edit_user=1` but `rol_administrator=0`.\n\n**Step 1:** Log in as the user manager account and capture the session cookie.\n\n**Step 2:** Request all users across all organizations by directly calling the data endpoint:\n```bash\ncurl -s -b \u0027PHPSESSID=\u003cuser_manager_session\u003e\u0027 \\\n  \u0027https://target/adm_program/modules/contacts/contacts_data.php?mem_show_filter=3\u0026draw=1\u0026start=0\u0026length=100\u0026search%5Bvalue%5D=\u0027\n```\n\n**Expected behavior:** The request should be rejected or return only current-organization users, since the user is not a full administrator and the frontend never offers filter=3 to non-administrators.\n\n**Actual behavior:** The endpoint returns a JSON response containing all users from ALL organizations in the database, including:\n- User UUIDs (`usr_uuid`)\n- Login names (`login_name`)\n- Email addresses (`member_email`)\n- All configured profile fields (names, addresses, phone numbers, etc.)\n\n**Step 3:** Verify that users from Organization B (where the attacker has no membership) appear in the results by checking the `member_this_orga` field \u2014 it will be `0` for cross-org users.\n\n## Impact\n\nIn multi-organization Admidio deployments (the primary use case for organization isolation), a user manager in one organization can exfiltrate the complete member directory of all other organizations sharing the same database. Exposed data includes:\n\n- Full names and all configured profile fields\n- Email addresses\n- Login names (useful for credential attacks)\n- User UUIDs (useful for targeting other API endpoints)\n\nThis completely bypasses the multi-tenant organization isolation boundary. The `contacts_show_all` admin setting (intended to control this feature) is also bypassed, meaning even instances where administrators have explicitly disabled cross-org viewing are affected.\n\n## Recommended Fix\n\nChange line 235 in `modules/contacts/contacts_data.php` to match the frontend guard at `contacts.php:80`:\n\n```php\n// Before (vulnerable):\n} elseif (($getMembersShowFilter === 3) \u0026\u0026 $gCurrentUser-\u003eisAdministratorUsers()) {\n\n// After (fixed):\n} elseif (($getMembersShowFilter === 3) \u0026\u0026 $gCurrentUser-\u003eisAdministrator() \u0026\u0026 $gSettingsManager-\u003egetBool(\u0027contacts_show_all\u0027)) {\n```\n\nAdditionally, as defense-in-depth, add an early rejection at the top of the file (after line 59) to block the filter value entirely for unauthorized users:\n\n```php\nif ($getMembersShowFilter === 3 \u0026\u0026 (!$gCurrentUser-\u003eisAdministrator() || !$gSettingsManager-\u003egetBool(\u0027contacts_show_all\u0027))) {\n    $getMembersShowFilter = 0; // Fall back to default\n}\n```",
  "id": "GHSA-g8p8-94f2-28gr",
  "modified": "2026-05-08T19:55:36Z",
  "published": "2026-04-29T21:44:24Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/Admidio/admidio/security/advisories/GHSA-g8p8-94f2-28gr"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-41657"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/Admidio/admidio"
    },
    {
      "type": "WEB",
      "url": "https://github.com/Admidio/admidio/releases/tag/v5.0.9"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Admidio Exposes Cross-Organization Member Data via Permission Check Mismatch in contacts_data.php"
}

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CVE-2026-41657 (GCVE-0-2026-41657)

FKIE_CVE-2026-41657

GHSA-G8P8-94F2-28GR

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