CVE-2026-76081: ZITADEL Improper Role Revocation On Granted Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-v859-c572-qh5p",
  "modified" : "2026-09-14T21:31:37Z",
  "published" : "2026-09-14T21:31:37Z",
  "aliases" : [ "CVE-2026-76081" ],
  "summary" : "ZITADEL: Improper Role Revocation on Granted Projects during Multiple Role Deletions",
  "details" : "### Summary\n\nA bug in how ZITADEL updates permissions when multiple project roles are deleted at the same time can cause some user permissions to be missed. This issue specifically affects **User Grants on Granted Projects** (projects shared between different organizations), **potentially** allowing users to keep access rights that were supposed to be completely removed.\n\n### Impact\n\nWhen an organization shares a project with another organization (a Project Grant), administrators can assign specific roles to users via a User Grant. If multiple roles are deleted from that project at the same time, a background process runs to strip those roles from the assigned users.\n\nBecause of an error in how ZITADEL loops through a user's list of roles during this specific cross-organization cleanup, deleting two or more roles at once **might** cause the system to accidentally skip over some of them.\n\n> **Scope Note:** This vulnerability only affects **User Grants on Granted Projects**. Direct project roles and global organization roles are not impacted.\n\nThe risk depends entirely on what the skipped role allowed the user to do—if it was an administrative or high-privilege role, the user **could potentially** retain those elevated permissions within that granted project even after the role was officially deleted.\n\n### Affected Versions\n\n* **4.x:** `4.0.0` through `4.15.3` (including RC versions)\n* **3.x:** `3.0.0` through `3.4.12` (including RC versions)\n\nNote: The 3.x release channel has reached End-of-Life (EOL) for security updates and will not receive a backported patch.\n\n### Patches & Resolution\n\nThis issue has been fully resolved in the latest releases.\n\nThe update fixes the role-removal logic to ensure no roles are skipped. Furthermore, **this patch includes an automatic database migration**. When you update, the system will automatically scan your database, find any user permissions on granted projects that **may** have been accidentally left behind by this bug, and correct them.\n\n- **4.x**: Upgrade to $\\ge$[4.16.0](https://github.com/zitadel/zitadel/releases/tag/v4.16.0)\n- **3.x**: Update to $\\ge$[4.16.0](https://github.com/zitadel/zitadel/releases/tag/v4.16.0) (or check out workarounds)\n\n### Workarounds\n\nThere are no configuration workarounds. Upgrading to a patched version is the recommended solution and only way to trigger the automatic cleanup migration. If you cannot upgrade immediately, we recommend manually reviewing user permissions specifically for your **Granted Projects** where multiple roles were recently deleted.\n\n### Questions\n\nIf you have any questions or comments about this advisory, please reach out to us at security@zitadel.com.\n\n### Credits\n\nThanks to [AyushParkara](https://github.com/AyushParkara)  for reporting this vulnerability.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:H/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/zitadel/zitadel"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "4.16.0"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/zitadel/zitadel/security/advisories/GHSA-v859-c572-qh5p"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/zitadel/zitadel/commit/9d60e83d6faa5e7e7a5339e031cdb26e0efe4d59"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/zitadel/zitadel"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/zitadel/zitadel/releases/tag/v4.16.0"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-193" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-09-14T21:31:37Z",
    "nvd_published_at" : null
  }
}