{"cve":"CVE-2026-47209","nvd":{"published":"2026-06-12T15:16:28.900","modified":"2026-10-26T11:10:00.157","status":"Deferred","description":"vm2 is an open source vm/sandbox for Node.js. Prior to version 3.11.4, the BaseHandler.set trap in bridge.js (line 1231) ignores the receiver parameter and unconditionally writes to the host target object. Per the Proxy set trap specification, when receiver !== proxy (e.g., when a child object inherits from the proxy via Object.create), the property assignment should create an own property on the receiver, not on the proxy target. The current implementation always calls otherReflectSet(object, key, value) against the host target, causing all inherited property writes to leak through to the host object. This bug provides an alternative attack vector for writing dangerous cross-realm Symbol keys (e.g., nodejs.util.promisify.custom) to host objects, bypassing any future per-trap isDangerousCrossRealmSymbol guard on the direct set path. This issue has been patched in version 3.11.4.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N","score":8.6},"cwes":["CWE-693"],"references":["https://github.com/patriksimek/vm2/commit/26d0318b5e6555be4b187ba05d6cf378ccecfe22","https://github.com/patriksimek/vm2/releases/tag/v3.11.4","https://github.com/patriksimek/vm2/security/advisories/GHSA-c4cf-2hgv-2qv6"],"products":[],"source":"nvd","synced_at":"2026-10-26T11:33:08.859761529+00:00"},"epss":{"cve":"CVE-2026-47209","score":0.00287,"percentile":0.21073,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-c4cf-2hgv-2qv6","url":"https://osv.dev/vulnerability/GHSA-c4cf-2hgv-2qv6","summary":"vm2's Bridge Proxy set trap ignores receiver parameter, enabling host object property injection via prototype chain","modified":"2026-06-12T19:45:09.843541948Z","packages":[{"ecosystem":"npm","name":"vm2","purl":"pkg:npm/vm2","ranges":["<3.11.4"],"fixed":["3.11.4"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}