{
  "cveId": "CVE-2026-33916",
  "url": "https://patchblox.com/security/cve/CVE-2026-33916",
  "summary": "CVE-2026-33916 is fixed in node-handlebars on 1 platform by DEBIAN-CVE-2026-33916 (version 3:4.7.9-1), released March 27, 2026. It is not reported as exploited. Patch Radar priority: Routine.",
  "title": "Handlebars.js has Prototype Pollution Leading to XSS through Partial Template Injection",
  "description": "Handlebars provides the power necessary to let users build semantic templates. In versions 4.0.0 through 4.7.8, \u0060resolvePartial()\u0060 in the Handlebars runtime resolves partial names via a plain property lookup on \u0060options.partials\u0060 without guarding against prototype-chain traversal. When \u0060Object.prototype\u0060 has been polluted with a string value whose key matches a partial reference in a template, the polluted string is used as the partial body and rendered without HTML escaping, resulting in reflected or stored XSS. Version 4.7.9 fixes the issue. Some workarounds are available. Apply \u0060Object.freeze(Object.prototype)\u0060 early in application startup to prevent prototype  pollution. Note: this may break other libraries, and/or use the Handlebars runtime-only build (\u0060handlebars/runtime\u0060), which does not compile templates  and reduces the attack surface.",
  "published": "2026-03-27T21:17:27Z",
  "severity": "Moderate",
  "cvss": 4.7,
  "cvssVector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N",
  "cwe": "Improper Neutralization of Input During Web Page Generation (\u0027Cross-site Scripting\u0027)",
  "epss": 0.0028,
  "epssPercentile": 0.20608,
  "priority": "Routine",
  "priorityTier": 4,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "vendorAdvisory": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-33916",
  "fixes": [
    {
      "platform": "linux",
      "product": "node-handlebars",
      "release": "Debian 14",
      "fixedVersion": "3:4.7.9-1",
      "fix": "DEBIAN-CVE-2026-33916",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-33916",
      "released": "2026-03-27T21:17:27Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-08T13:06:02Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}