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.
References
Configurations
No configuration.
History
17 Sep 2026, 14:18
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-09-17 14:18
Updated : 2026-09-17 14:18
NVD link : CVE-2026-92959
Mitre link : CVE-2026-92959
CVE.ORG link : CVE-2026-92959
JSON object : View
Products Affected
No product.
CWE
CWE-693
Protection Mechanism Failure
