Craft CMS has a Missing Authorization Check on User Group Removal via save-permissions Action

{
  "id": "ac36c36f7b5be009009dbb4635a042c14574796735c197e591af62eccb296e2c",
  "url": "https://osv.dev/vulnerability/CVE-2026-41128",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Craft CMS has a Missing Authorization Check on User Group Removal via save-permissions Action",
    "summary": "Craft CMS is a content management system (CMS). In versions 5.6.0 through 5.9.14, the `actionSavePermissions()` endpoint allows a user with only `viewUsers` permission to remove arbitrary users from all user groups. While `_saveUserGroups()` enforces per-group authorization for additions, it performs no equivalent authorization check for removals, so submitting an empty `groups` value removes all existing group memberships. Version 5.9.15 contains a patch.",
    "evidence": "osv:CVE-2026-41128",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2026-41128",
      "aliases": [
        "CVE-2026-41128",
        "GHSA-jq2f-59pj-p3m3"
      ],
      "metrics": [
        {
          "type": "CVSS_V4",
          "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/craftcms/cms",
              "type": "GIT",
              "events": [
                {
                  "introduced": "e14cba6cdca8902c3efb0549a5dc290002b750c2"
                },
                {
                  "fixed": "84d783586bf0abf619a9d1909d93fdfdcaaf73a4"
                },
                {
                  "fixed": "b135384808ad43fcf8836a9dd9b877fb0087bc27"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "5.6.0"
                      },
                      {
                        "fixed": "5.9.15"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StringRangeExpression"
                  },
                  {
                    "range": [
                      {
                        "fixed": "b135384808ad43fcf8836a9dd9b877fb0087bc27"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  }
                ]
              }
            }
          ],
          "versions": [
            "5.9.14",
            "5.9.13",
            "5.9.3",
            "5.9.12",
            "5.9.11",
            "5.9.10",
            "5.9.9",
            "5.9.8",
            "5.9.7",
            "5.9.6",
            "5.9.5",
            "5.9.4",
            "5.9.2",
            "5.9.1",
            "5.9.0",
            "5.9.0-beta.2",
            "5.9.0-beta.1",
            "5.8.23",
            "5.8.22",
            "5.8.21",
            "5.8.20",
            "5.8.19",
            "5.8.18",
            "5.8.17",
            "5.8.16",
            "5.8.15",
            "5.8.14",
            "5.8.13.2",
            "5.8.13.1",
            "5.8.13",
            "5.8.12",
            "5.8.11",
            "5.8.10",
            "5.8.9",
            "5.8.8",
            "5.8.7",
            "5.8.6",
            "5.8.5",
            "5.8.4",
            "5.8.3",
            "5.8.2",
            "5.8.1",
            "5.8.0",
            "5.7.11",
            "5.7.10",
            "5.7.9",
            "5.7.8.2",
            "5.7.8.1",
            "5.7.8",
            "5.7.7",
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            "5.7.5",
            "5.7.4",
            "5.7.3",
            "5.7.2",
            "5.7.1.1",
            "5.7.1",
            "5.7.0",
            "5.6.17",
            "5.6.16",
            "5.6.15",
            "5.6.14",
            "5.6.13",
            "5.6.12",
            "5.6.11",
            "5.6.10.2",
            "5.6.10.1",
            "5.6.10",
            "5.6.9.1",
            "5.6.9",
            "5.6.8",
            "5.6.7",
            "5.6.6",
            "5.6.5.1",
            "5.6.5",
            "5.6.4",
            "5.6.3",
            "5.6.2",
            "5.6.1",
            "5.6.0.2",
            "5.6.0.1",
            "5.6.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-41128.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:32.820392788Z",
      "provider": "osv",
      "references": [
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/41xxx/CVE-2026-41128.json",
        "https://github.com/craftcms/cms/security/advisories/GHSA-jq2f-59pj-p3m3",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-41128",
        "https://github.com/craftcms/cms/commit/b135384808ad43fcf8836a9dd9b877fb0087bc27"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-862"
        ],
        "cna_assigner": "GitHub_M",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/41xxx/CVE-2026-41128.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-41128",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 499935,
  "published_at": "2026-04-21T23:32:37.911+00:00"
}