CVE-2026-28685: Kimai/kimai Kimai's API Invoice Endpoint Missing Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-v33r-r6h2-8wr7",
  "modified" : "2026-03-06T15:17:08Z",
  "published" : "2026-03-04T20:43:17Z",
  "aliases" : [ "CVE-2026-28685" ],
  "summary" : "Kimai's API invoice endpoint missing customer-level access control (IDOR)",
  "details" : "## Summary\n\n`GET /api/invoices/{id}` only checks the role-based `view_invoice` permission but does not verify the requesting user has `access` to the invoice's customer. Any user with `ROLE_TEAMLEAD` (which grants `view_invoice`) can read all invoices in the system, including those belonging to customers assigned to other teams.\n\n## Affected Code\n\n`src/API/InvoiceController.php` line 92-101:\n\n```php\n#[IsGranted('view_invoice')]           // Role check only, no customer access check\n#[Route(methods: ['GET'], path: '/{id}', name: 'get_invoice', requirements: ['id' => '\\d+'])]\npublic function getAction(Invoice $invoice): Response\n{\n    $view = new View($invoice, 200);\n    $view->getContext()->setGroups(self::GROUPS_ENTITY);\n    return $this->viewHandler->handle($view);  // Returns ANY invoice by ID\n}\n```\n\nThe web controller (`src/Controller/InvoiceController.php` line 304-307) correctly checks customer access:\n\n```php\n#[IsGranted('view_invoice')]\n#[IsGranted(new Expression(\"is_granted('access', subject.getCustomer())\"), 'invoice')]\npublic function downloadAction(Invoice $invoice, ...): Response { ... }\n```\n\nThe `access` attribute in `CustomerVoter` (line 71-87) verifies team membership, but this check is entirely missing from the API endpoint.\n\n## PoC\n\nTested against Kimai v2.50.0 (Docker: `kimai/kimai2:apache`).\n\nSetup:\n- TeamA with CustomerA (\"SecretCorp\"), TeamB with CustomerB (\"BobCorp\")\n- Bob is a teamlead in TeamB only\n- An invoice exists for SecretCorp (TeamA)\n\n```bash\n# Bob (TeamB) reads SecretCorp (TeamA) invoice\ncurl -H \"Authorization: Bearer BOB_TOKEN\" http://localhost:8888/api/invoices/1\n```\n\nResponse (200 OK):\n```json\n{\n  \"invoiceNumber\": \"INV-2026-001\",\n  \"total\": 15000.0,\n  \"currency\": \"USD\",\n  \"customer\": {\"name\": \"SecretCorp\", ...}\n}\n```\n\nBob can also enumerate all invoices via `GET /api/invoices` — the list endpoint uses `setCurrentUser()` in the query but the single-item endpoint bypasses this entirely via Symfony ParamConverter.\n\n## Impact\n\nAny teamlead can read all invoices across the system regardless of team assignment. Invoice data typically contains sensitive financial information (amounts, customer details, payment terms). In multi-team deployments this breaks the intended data isolation between teams.\n\n## Suggested Fix\n\nAdd the customer access check to the API endpoint, matching the web controller:\n\n```diff\n #[IsGranted('view_invoice')]\n+#[IsGranted(new Expression(\"is_granted('access', subject.getCustomer())\"), 'invoice')]\n #[Route(methods: ['GET'], path: '/{id}', name: 'get_invoice')]\n public function getAction(Invoice $invoice): Response\n```",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Packagist",
      "name" : "kimai/kimai"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "2.51.0"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 2.50.0"
    }
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/kimai/kimai/security/advisories/GHSA-v33r-r6h2-8wr7"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-28685"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/kimai/kimai/commit/a0601c8cb28fed1cca19051a8272425069ab758f"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/kimai/kimai"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/kimai/kimai/releases/tag/2.51.0"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-285", "CWE-862" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-03-04T20:43:17Z",
    "nvd_published_at" : "2026-03-06T05:16:38Z"
  }
}