Security advisory

{
  "id": "6a8b089c54faec2873f094e70eb7bce37fc02e73f9568190cfb3194b53cf18eb",
  "url": "https://osv.dev/vulnerability/CVE-2019-20920",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2019-20920",
    "summary": "Handlebars before 3.0.8 and 4.x before 4.5.3 is vulnerable to Arbitrary Code Execution. The lookup helper fails to properly validate templates, allowing attackers to submit templates that execute arbitrary JavaScript. This can be used to run arbitrary code on a server processing Handlebars templates or in a victim's browser (effectively serving as XSS).",
    "evidence": "osv:CVE-2019-20920",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2019-20920",
      "aliases": [
        "CVE-2019-20920",
        "GHSA-3cqr-58rm-57f8",
        "SNYK-JS-HANDLEBARS-534478"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:L/A:L"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/handlebars-lang/handlebars.js",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "16bd606fec0ada4c811eb7afe6bfd619d88f3d37"
                },
                {
                  "introduced": "bff5fab8f9d42e21950be00dcf1cedf4dc1a565b"
                },
                {
                  "fixed": "c819c8b533934d2ac18001d7eb27a3205b00c2f3"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:handlebarsjs:handlebars:*:*:*:*:*:node.js:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "3.0.8"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "cpe": "cpe:2.3:a:handlebarsjs:handlebars:*:*:*:*:*:node.js:*:*",
                    "range": [
                      {
                        "introduced": "4.0.0"
                      },
                      {
                        "fixed": "4.5.3"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v3.0.7",
            "v4.5.2",
            "v4.5.1",
            "v4.5.0",
            "v4.4.3",
            "v4.4.2",
            "v4.4.1",
            "v4.2.1",
            "v4.3.4",
            "v4.4.0",
            "v4.3.3",
            "v4.3.2",
            "v4.3.1",
            "v4.3.0",
            "v4.2.0",
            "v4.1.2-0",
            "v4.1.2",
            "v1.3.0",
            "v4.1.1",
            "v4.0.12",
            "v3.0.6",
            "v3.0.5",
            "v3.0.4",
            "v4.0.11",
            "v4.0.10",
            "v4.0.9",
            "v4.0.8",
            "v4.0.7",
            "v4.0.6",
            "v4.0.5",
            "v3.0.3",
            "v4.0.4",
            "v4.0.3",
            "v4.0.2",
            "v4.0.1",
            "v4.0.0",
            "v3.0.2",
            "v3.0.1",
            "v3.0.0",
            "v2.0.0",
            "v2.0.0-beta.1",
            "v2.0.0-alpha.4",
            "v2.0.0-alpha.3",
            "v2.0.0-alpha.2",
            "v2.0.0-alpha.1",
            "v1.2.1",
            "v1.2.0",
            "v1.1.2",
            "v1.1.1",
            "v1.1.0",
            "v1.0.12",
            "1.0.0",
            "v1.0.11",
            "1.0.0-rc.4",
            "v1.0.10",
            "v1.0.9",
            "1.0.0-rc.3",
            "v1.0.8",
            "1.0.rc.2",
            "v1.0.6-2",
            "v1.0.6",
            "v1.0.6beta",
            "1.0.0.beta.1",
            "0.9.0.pre.4"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2019-20920.json"
          }
        }
      ],
      "modified": "2026-10-24T10:30:28.950515041Z",
      "provider": "osv",
      "references": [
        "https://snyk.io/vuln/SNYK-JS-HANDLEBARS-534478",
        "https://www.npmjs.com/advisories/1324",
        "https://www.npmjs.com/advisories/1316"
      ],
      "provider_metadata": {}
    },
    "related_cves": [
      {
        "value": "CVE-2019-20920",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 432177,
  "published_at": "2020-09-30T18:15:17.927+00:00"
}