Solution

{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 2.56.0"
      },
      "package": {
        "ecosystem": "Packagist",
        "name": "kimai/kimai"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.57.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-52826"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-285",
      "CWE-639"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-07-14T00:09:35Z",
    "nvd_published_at": null,
    "severity": "MODERATE"
  },
  "details": "### Summary\n\nKimai 2.56.0 contains an authenticated improper authorization vulnerability in the Web rate editing flows for projects, customers, and activities. A user who can edit one authorized parent object can combine that authorized parent ID with the rate ID of a different, unauthorized parent object and thereby modify the unauthorized rate record.\n\nThis affects `ProjectRate`, `CustomerRate`, and `ActivityRate` editing. The issue is caused by missing parent-child consistency validation and allows cross-project, cross-customer, or cross-activity tampering of billing-related configuration.\n\n### Details\n\nThe issue affects the following Web routes:\n\n- `GET/POST /en/admin/project/{id}/rate/{rate}`\n- `GET/POST /en/admin/customer/{id}/rate/{rate}`\n- `GET/POST /en/admin/activity/{id}/rate/{rate}`\n\nIn both cases, the parent object and the rate object are resolved independently from user-controlled route parameters. The controller only checks whether the current user may edit the parent object referenced by `{id}`, but it does not verify that the child rate object referenced by `{rate}` actually belongs to that same parent.\n\nIn these controllers, there is no validation such as:\n\n- `$rate-\u003egetProject() === $project`\n- `$rate-\u003egetCustomer() === $customer`\n- `$rate-\u003egetActivity() === $activity`\n\nThis missing binding check is especially notable because the API delete endpoints already enforce the expected parent-child relationship.\n\nThis shows that parent-child consistency is already a recognized invariant in the application design, but the Web edit endpoints fail to enforce it for projects, customers, and activities.\n\n*A PoC was provided, but removed for security reasons.*\n\n### Impact\n\nThis vulnerability allows authenticated users to tamper with billing-related rate configuration outside their authorized project, customer, or activity scope. An attacker can modify rate values belonging to other teams or business domains, which can affect time-based settlement, inherited pricing, cost calculations, budget reporting, revenue reporting, and downstream invoice generation.\n\nBecause the issue directly persists changes into `kimai2_projects_rates`, `kimai2_customers_rates`, and `kimai2_activities_rates`, it is a real cross-scope integrity vulnerability rather than a UI-only flaw. The attack breaks team-based isolation boundaries for high-value financial configuration.\n\n# Solution\n\nThe rate edit forms for `customers`, `projects` and `activities` now verify that the rate belongs to the parent referenced in the URL and reject the request otherwise.\n\nSee [https://www.kimai.org/en/security/ghsa-2xgg-2x8h-8xw4](https://www.kimai.org/en/security/ghsa-2xgg-2x8h-8xw4) for more information.",
  "id": "GHSA-2xgg-2x8h-8xw4",
  "modified": "2026-07-14T00:09:35Z",
  "published": "2026-07-14T00:09:35Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/kimai/kimai/security/advisories/GHSA-2xgg-2x8h-8xw4"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/kimai/kimai"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Kimai: Improper Authorization in Project, Customer, and Activity Rate Edit Endpoints Allows Cross-Scope Rate Manipulation"
}