CVE-2026-76819: Nuclei Arbitrary Code Execution Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-vxg7-f2jj-jmqm",
  "modified" : "2026-09-22T20:37:14Z",
  "published" : "2026-09-22T20:37:13Z",
  "aliases" : [ "CVE-2026-76819" ],
  "summary" : "Nuclei: Arbitrary Code Execution via Goja JavaScript Engine Vulnerability",
  "details" : "A vulnerability in the Goja JavaScript engine used by Nuclei's `javascript:` protocol allows arbitrary native code execution on the scanner host when running untrusted JavaScript templates.\n\n**Affected Component**\n\nThe issue is in the Goja JavaScript runtime embedded in Nuclei's JavaScript protocol (`pkg/js/`). An out-of-bounds heap write in the engine can be exploited to achieve native code execution during template evaluation.\n\n**Description**\n\nNuclei uses the Goja engine to execute `javascript:` protocol templates. A memory safety vulnerability in Goja allows attacker-controlled JavaScript to corrupt heap memory and execute arbitrary native code on the host running Nuclei.\n\nBecause `javascript:` templates execute without the `-code` flag and unsigned JavaScript templates run by default, a malicious template from an untrusted source can trigger code execution during a normal scan. The vulnerability could also be reached through a template's `init` section, which runs during template initialization before other security checks complete.\n\n> [!NOTE]\nJavaScript templates do not require the `-code` flag and are not subject to the code-template signing requirement on affected versions. Nuclei v3.11.0 adds a separate signing requirement for JavaScript templates as additional defense in depth.\n\n**Affected Users**\n\n- **CLI users** running untrusted or third-party `javascript:` templates.\n- **SDK users** who integrate Nuclei into platforms where end users can supply JavaScript templates.\n\n**Patches**\n\n- The vulnerability is fixed in Nuclei v3.10.0 by updating the Goja dependency. Upgrading is strongly recommended.\n- Fix reference: https://github.com/projectdiscovery/nuclei/pull/7467\n- Additional hardening in v3.11.0 requires cryptographic signatures for JavaScript templates: https://github.com/projectdiscovery/nuclei/pull/7514\n\n**Mitigation**\n\nUpgrade to Nuclei v3.10.0 or later. For additional protection, upgrade to v3.11.0 where JavaScript templates also require valid signatures.\n\nIn the meantime, avoid running JavaScript templates from unverified sources.\n\n**Workarounds**\n\nIf upgrading is not an option, do not run untrusted JavaScript templates. There is no configuration flag that mitigates native code execution on affected versions.\n\n**Acknowledgments**\n\nThanks to Dylan Pindur ([@dpindur](https://github.com/dpindur)) and Adam Kues ([@akues-an](https://github.com/akues-an)) of the Assetnote security research team for reporting this issue through responsible disclosure via security@projectdiscovery.io.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/projectdiscovery/nuclei/v3"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "3.0.0"
      }, {
        "fixed" : "3.10.0"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/projectdiscovery/nuclei/security/advisories/GHSA-vxg7-f2jj-jmqm"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-76819"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/projectdiscovery/nuclei/pull/7467"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/projectdiscovery/nuclei/pull/7514"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/projectdiscovery/nuclei/commit/1fe6025b966cbb95ed4d9f40abfb629b6cbd27b2"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/projectdiscovery/nuclei"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/projectdiscovery/nuclei/releases/tag/v3.10.0"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-787", "CWE-94" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-09-22T20:37:13Z",
    "nvd_published_at" : "2026-09-22T17:17:25Z"
  }
}