CVE-2026-76802: Nuclei Arbitrary Command Execution Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-jpf4-98qj-qr67",
  "modified" : "2026-09-22T20:37:16Z",
  "published" : "2026-09-22T20:37:16Z",
  "aliases" : [ "CVE-2026-76802" ],
  "summary" : "Nuclei: Arbitrary Command Execution via DAST Code Signature Bypass",
  "details" : "A vulnerability in Nuclei's DAST template loading path allows unsigned `code:` protocol templates to execute, bypassing the cryptographic signature requirement that is meant to prevent arbitrary command execution from untrusted templates.\n\n**Affected Component**\n\nThe issue is in the template loader's DAST loading branch. When `-dast` is enabled and a template contains a `fuzzing:` block, the loader accepted the template through a code path that omitted the unsigned-code-template signature check present in the normal loading branch.\n\n**Description**\n\nNuclei requires `code:` protocol templates to be cryptographically signed before execution. Unsigned code templates are normally skipped with a warning. However, when a template combined a `fuzzing:` block (making it DAST-eligible) with an unsigned `code:` block, enabling `-dast` routed the template through the DAST loader branch, which did not enforce signature verification.\n\nFor multiprotocol templates containing both HTTP and `code:` blocks, the unsigned code request was included in the execution queue regardless of whether `-code` was set. This allowed arbitrary shell command execution from an unsigned `code:` block with only `-dast` enabled.\n\n> [!NOTE]\nBoth DAST mode (`-dast`) and code-protocol templates are disabled by default. Code templates normally require both the `-code` flag and a valid template signature. This issue bypassed the signature and `-code` controls only when `-dast` was explicitly enabled.\n\n**Affected Users**\n\n- **CLI users** running DAST/fuzzing scans (`-dast`) with untrusted or attacker-supplied templates that contain both `fuzzing:` and `code:` blocks.\n- **SDK users** who integrate Nuclei with DAST mode enabled and allow end users to supply custom templates.\n\n**Patches**\n\n- The vulnerability is fixed in Nuclei v3.10.0. Upgrading is strongly recommended.\n- Fix reference: https://github.com/projectdiscovery/nuclei/pull/7472\n\n**Mitigation**\n\nUpgrade to Nuclei v3.10.0, where code template signature verification is enforced before DAST loading.\n\nIn the meantime, avoid running DAST scans with untrusted templates.\n\n**Workarounds**\n\nIf upgrading is not an option, do not use `-dast` with templates from unverified sources.\n\n**Acknowledgments**\n\nThanks to @daffainfo for reporting this issue.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N"
  } ],
  "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-jpf4-98qj-qr67"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-76802"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/projectdiscovery/nuclei/pull/7472"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/projectdiscovery/nuclei/commit/1c440e755a97471c56fb0276ee8a8c4132974645"
  }, {
    "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-78" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-09-22T20:37:16Z",
    "nvd_published_at" : "2026-09-22T17:17:24Z"
  }
}