Security advisory

{
  "id": "dc705a0d88ffe86b4dbfbc0d1cb4fea20bc44aa788e71bfc1b9cada542eaad71",
  "url": "https://osv.dev/vulnerability/CVE-2021-20088",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2021-20088",
    "summary": "Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') in mootools-more 1.6.0 allows a malicious user to inject properties into Object.prototype.",
    "evidence": "osv:CVE-2021-20088",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2021-20088",
      "aliases": [
        "CVE-2021-20088",
        "GHSA-fw45-938v-p26j"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/mootools/mootools-more",
              "type": "GIT",
              "events": [
                {
                  "introduced": "bf233fb08b9ee5e6ec0098292540aa6b79b486cc"
                },
                {
                  "last_affected": "bf233fb08b9ee5e6ec0098292540aa6b79b486cc"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:mootools:mootools-more:1.6.0:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "1.6.0"
                      },
                      {
                        "last_affected": "1.6.0"
                      }
                    ],
                    "source": "CPE_STRING"
                  }
                ]
              }
            }
          ],
          "versions": [
            "1.6.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-20088.json"
          }
        }
      ],
      "modified": "2026-10-24T10:30:33.990449488Z",
      "provider": "osv",
      "references": [
        "https://github.com/BlackFan/client-side-prototype-pollution/blob/master/pp/mootools-more.md"
      ],
      "provider_metadata": {}
    },
    "related_cves": [
      {
        "value": "CVE-2021-20088",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 433414,
  "published_at": "2021-04-23T18:15:08.097+00:00"
}