Velocity.js: Remote Code Execution via property-read to Function constructor (bypass of CVE-2026-44966 fix)

{
  "id": "b155a869cde468bd840df93f3ceddcdb8b58298a4600c3413b24b712d0bed5b5",
  "url": "https://osv.dev/vulnerability/CVE-2026-73649",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Velocity.js: Remote Code Execution via property-read to Function constructor (bypass of CVE-2026-44966 fix)",
    "summary": "Velocity.js is a JavaScript implementation of the Apache Velocity template engine. Prior to 2.1.7, the earlier fix for CVE-2026-44966 filtered constructor, __proto__, and prototype only in the #set assignment handler in src/compile/set.ts, while property-read expressions in src/compile/references.ts remained unfiltered. The getReferences() flow called getAttributes(), whose property access allowed an attacker-controlled template to traverse constructor.constructor to the JavaScript Function constructor. The #set handler validated only the assignment target and did not inspect the right-hand property-read expression, allowing arbitrary shell commands, environment-variable access, cloud-credential access, and internal-network access in the server process. This issue is fixed in version 2.1.7.",
    "evidence": "osv:CVE-2026-73649",
    "products": [],
    "severity": "critical",
    "structured": {
      "id": "CVE-2026-73649",
      "aliases": [
        "CVE-2026-73649",
        "GHSA-7gfh-x38p-prh3"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/shepherdwind/velocity.js",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "de81a8efae35da7e9b1b159597f5b3162e714329"
                },
                {
                  "fixed": "f8e47a6c4607249b9c967d3a1ced959b4dd64dba"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "2.1.7"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StringRangeExpression"
                  },
                  {
                    "range": [
                      {
                        "fixed": "f8e47a6c4607249b9c967d3a1ced959b4dd64dba"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  },
                  {
                    "range": [
                      {
                        "fixed": "de81a8efae35da7e9b1b159597f5b3162e714329"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "v2.1.7"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v2.1.6",
            "v2.1.5",
            "v2.1.4",
            "v2.1.3",
            "v2.1.2",
            "v2.1.1",
            "v2.1.0",
            "v2.0.6",
            "v2.0.5",
            "v2.0.4",
            "v2.0.3",
            "v2.0.2",
            "v2.0.1",
            "list",
            "v1.1.5",
            "v1.1.3",
            "v1.1.2",
            "v1.1.1",
            "v1.1.0",
            "v1.0.2",
            "v1.0.1",
            "v1.0.0",
            "v0.10.1",
            "0.10.0",
            "v0.9.6",
            "v0.9.5",
            "v0.9.4",
            "v0.9.3",
            "v0.9.2",
            "0.9.1",
            "0.9.0",
            "0.8.5",
            "0.8.4",
            "0.8.2",
            "0.8.0",
            "0.7.5",
            "0.7.4",
            "0.7.3",
            "0.7.2",
            "0.6.0",
            "0.4.10",
            "0.4.9",
            "0.4.8",
            "0.4.7",
            "0.4.5",
            "0.4.4",
            "0.4.2",
            "0.4.1",
            "0.4.0",
            "0.3.16",
            "0.3.15",
            "0.3.14",
            "0.3.13",
            "0.3.12"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-73649.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:52.156569676Z",
      "provider": "osv",
      "references": [
        "https://github.com/shepherdwind/velocity.js/releases/tag/v2.1.7",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/73xxx/CVE-2026-73649.json",
        "https://github.com/shepherdwind/velocity.js/security/advisories/GHSA-7gfh-x38p-prh3",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-73649",
        "https://github.com/shepherdwind/velocity.js/commit/f8e47a6c4607249b9c967d3a1ced959b4dd64dba",
        "https://github.com/shepherdwind/velocity.js/pull/192"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-94"
        ],
        "cna_assigner": "GitHub_M",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/73xxx/CVE-2026-73649.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-73649",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 520984,
  "published_at": "2026-08-13T18:05:31.929+00:00"
}