Nuclei: Environment Variable Disclosure via Response-Derived Data in DAST/Fuzz Mode

{
  "id": "bcbf85ca4891ee142346eedc6b6db8fcdb0f8f25c0cb2e3bdbfb7f75d2731ef7",
  "url": "https://osv.dev/vulnerability/CVE-2026-76805",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Nuclei: Environment Variable Disclosure via Response-Derived Data in DAST/Fuzz Mode",
    "summary": "Nuclei is a vulnerability scanner built on a simple YAML-based DSL. From 3.0.0 until 3.10.0, the DAST/fuzz payload path in pkg/fuzz/parts.go can evaluate substituted runtime data more than once, creating a second evaluation pass that allows response content captured by an internal: true extractor in one protocol step to be reinterpreted as template syntax in a later fuzz step. This vulnerability is an incomplete fix for CVE-2026-41645: the prior remediation made expressions.Evaluate() single-pass within one call but did not prevent DAST/fuzz callers from evaluating substituted output again. When -env-vars is enabled, a malicious scan target can return marker-shaped content that resolves against the template variable map and discloses scanner-host environment variables such as credentials, API keys, or tokens. The vulnerability requires a multi-step DAST or fuzz template, response data reused through an internal extractor, and explicit environment-variable expansion; users who do not enable -env-vars are not affected by the sensitive-information disclosure. This issue is fixed in version 3.10.0.",
    "evidence": "osv:CVE-2026-76805",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2026-76805",
      "aliases": [
        "CVE-2026-76805",
        "GHSA-jpvm-9frm-hjcq",
        "GO-2026-6571"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/projectdiscovery/nuclei",
              "type": "GIT",
              "events": [
                {
                  "introduced": "990cec0de154bd3955e0c1e19951f90e06f6ea7c"
                },
                {
                  "fixed": "f9cf234c12a333656751e04493dc4b1f4f5f3e88"
                },
                {
                  "fixed": "ccbfb12bd01447ba25f6e755dfb2bee677736da6"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "3.0.0"
                      },
                      {
                        "fixed": "3.10.0"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StringRangeExpression"
                  },
                  {
                    "range": [
                      {
                        "fixed": "ccbfb12bd01447ba25f6e755dfb2bee677736da6"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  },
                  {
                    "range": [
                      {
                        "fixed": "f9cf234c12a333656751e04493dc4b1f4f5f3e88"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "v3.10.0"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v3.9.0",
            "v3.8.0",
            "v3.7.1",
            "v3.7.0",
            "v3.6.2",
            "v3.6.1",
            "v3.6.0",
            "v3.5.1",
            "v3.5.0",
            "v3.4.10",
            "v3.4.9",
            "v3.4.8",
            "v3.4.7",
            "v3.4.6",
            "v3.4.5",
            "v3.4.4",
            "v3.4.3",
            "v3.4.2",
            "v3.4.1",
            "v3.4.0",
            "v3.3.10",
            "v3.3.9",
            "v3.3.8",
            "v3.3.7",
            "v3.3.6",
            "v3.3.5",
            "v3.3.4",
            "v3.3.3",
            "v3.3.2",
            "v3.3.1",
            "v3.3.0",
            "v3.2.9",
            "v3.2.8",
            "v3.2.7",
            "v3.2.6",
            "v3.2.5",
            "v3.2.4",
            "v3.2.3",
            "v3.2.2",
            "v3.2.1",
            "v3.2.0",
            "v3.1.10",
            "v3.1.9",
            "v3.1.8",
            "v3.1.7",
            "v3.1.6",
            "v3.1.5",
            "v3.1.4",
            "v3.1.3",
            "v3.1.2",
            "v3.1.1",
            "v3.1.0",
            "v3.0.4",
            "v3.0.3",
            "v3.0.2",
            "v3.0.1",
            "v3.0.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-76805.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:50.218675223Z",
      "provider": "osv",
      "references": [
        "https://github.com/projectdiscovery/nuclei/releases/tag/v3.10.0",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/76xxx/CVE-2026-76805.json",
        "https://github.com/projectdiscovery/nuclei/security/advisories/GHSA-jpvm-9frm-hjcq",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-76805",
        "https://github.com/projectdiscovery/nuclei/commit/ccbfb12bd01447ba25f6e755dfb2bee677736da6",
        "https://github.com/projectdiscovery/nuclei/pull/7499"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-200"
        ],
        "cna_assigner": "GitHub_M",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/76xxx/CVE-2026-76805.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-76805",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 518915,
  "published_at": "2026-09-22T16:48:49.791+00:00"
}