{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "cpe": "cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*",
            "extracted_events": [
              {
                "introduced": "10.11.0"
              },
              {
                "fixed": "10.11.23"
              },
              {
                "introduced": "11.7.0"
              },
              {
                "fixed": "11.7.8"
              },
              {
                "introduced": "11.8.0"
              },
              {
                "fixed": "11.8.5"
              },
              {
                "introduced": "11.9.0"
              },
              {
                "fixed": "11.9.1"
              }
            ],
            "source": "CPE_RANGE"
          },
          "events": [
            {
              "introduced": "5b955468ea1ea8b56c0fb10feb258a36a767d7bb"
            },
            {
              "fixed": "075d003e1391ff0b24eca1e63b0222eb46eaded6"
            },
            {
              "introduced": "a9e574a82633915f22071f0d7ca2b006f249ec2a"
            },
            {
              "fixed": "d42004bb3046de3ed176938a34b1a70c1c3d9421"
            },
            {
              "introduced": "e8bd2b8a871cbeff6943bead62328478118188df"
            },
            {
              "fixed": "d9c17e42b19c27dfac0ebe6840d954a41e626890"
            },
            {
              "introduced": "583461af10fc9b2aef2871c722fc4376db695832"
            },
            {
              "fixed": "1f738d345805168964a55e5860aac9c747dceb78"
            }
          ],
          "repo": "https://github.com/mattermost/mattermost",
          "type": "GIT"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Mattermost",
    "cwe_ids": [
      "CWE-639"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/9xxx/CVE-2026-9812.json",
    "unresolved_ranges": [
      {
        "extracted_events": [
          {
            "introduced": "11.8.0"
          },
          {
            "last_affected": "11.8.4"
          },
          {
            "introduced": "11.7.0"
          },
          {
            "last_affected": "11.7.7"
          },
          {
            "introduced": "10.11.0"
          },
          {
            "last_affected": "10.11.22"
          },
          {
            "introduced": "11.9.0"
          },
          {
            "last_affected": "11.9.0"
          }
        ],
        "source": "AFFECTED_FIELD"
      }
    ]
  },
  "details": "Mattermost versions 11.9.x \u003c= 11.9.0, 11.8.x \u003c= 11.8.4, 11.7.x \u003c= 11.7.7, 10.11.x \u003c= 10.11.22 fail to validate that a property field belongs to the specified run before updating its value which allows an authenticated user with run property-management access to crash the Playbooks plugin via a REST request referencing a property field that belongs to a different run. Mattermost Advisory ID: MMSA-2026-00684",
  "id": "CVE-2026-9812",
  "modified": "2026-10-08T02:30:33.549632685Z",
  "published": "2026-09-14T10:43:45.589Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/9xxx/CVE-2026-9812.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://mattermost.com/security-updates"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-9812"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Missing property field ownership validation in Playbooks run property update endpoint"
}