{"cve":"CVE-2026-92959","nvd":{"published":"2026-09-17T14:18:02.130","modified":"2026-09-21T21:17:16.917","status":"Deferred","description":"vm2 before 3.11.8 does not fully enforce the allowAsync: false option in VM and NodeVM. While localPromise.prototype.then is replaced with a handler that throws 'Async not available', the sandbox's Promise static methods (Promise.resolve, Promise.all, Promise.race, Promise.any, and Promise.allSettled) still assimilate attacker-supplied thenables: native promise resolution performs PromiseResolveThenableJob and invokes the sandboxed code's then method in a microtask without passing through the patched then, so the async restriction is never applied. As a result, sandboxed script can schedule work that runs after VM.run() or NodeVM.run() has returned and outside the configured timeout, continuing to execute after the host believes execution is complete.","cvss_v4":{"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N","score":7.1},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H","score":7.1},"cwes":["CWE-693"],"references":["https://github.com/patriksimek/vm2/security/advisories/GHSA-f8gf-w286-fmq2","https://www.vulncheck.com/advisories/vm2-before-3.11.8-allowasync-bypass-via-promise-thenable","https://github.com/patriksimek/vm2/security/advisories/GHSA-f8gf-w286-fmq2"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:55:23.253742848+00:00"},"epss":{"cve":"CVE-2026-92959","score":0.00449,"percentile":0.39011,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-f8gf-w286-fmq2","url":"https://osv.dev/vulnerability/GHSA-f8gf-w286-fmq2","summary":"vm2: `allowAsync: false` can be bypassed through Promise thenable assimilation in VM and NodeVM","modified":"2026-10-05T23:00:04.244128331Z","packages":[{"ecosystem":"npm","name":"vm2","purl":"pkg:npm/vm2","ranges":["<3.11.8"],"fixed":["3.11.8"]}]}],"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."]}