vm2 (npm) versions 3.12.0 and earlier contain a sandbox escape in `VM` and `NodeVM`. When an embedder exposes a host API that returns a host-realm Promise, the bridge's rejection sanitizer (hostPromiseSanitizeReject / makeSanitizedPromiseCallback / normalizeHostPromiseCallbacks in lib/bridge.js) only wraps `then`/`catch` rejection slots that hold a function, and the sandbox-side `Symbol.species`/`.then` neutralization is installed only on the sandbox intrinsic `Promise.prototype`, so it never applies to a host Promise. Code running inside the sandbox can overwrite `p.constructor[Symbol.species]` on the host Promise and then call `p.then()` with no `onRejected` handler; V8 substitutes its internal Thrower, which re-throws the raw host rejection value into a resolve/reject closure captured by the attacker. This delivers an unsanitized, fully functional bridge proxy of the host object to sandboxed code, bypassing handleException and hostPromiseSanitizeReject. If the rejection value is host-pivotable (for example a host `process` object), this results in arbitrary code execution on the host. Fixed in 3.12.1.
References
Configurations
No configuration.
History
18 Sep 2026, 18:18
| Type | Values Removed | Values Added |
|---|---|---|
| References | () https://github.com/patriksimek/vm2/security/advisories/GHSA-6454-5x88-m6jw - |
18 Sep 2026, 14:19
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-09-18 14:19
Updated : 2026-09-18 18:18
NVD link : CVE-2026-93606
Mitre link : CVE-2026-93606
CVE.ORG link : CVE-2026-93606
JSON object : View
Products Affected
No product.
CWE
CWE-693
Protection Mechanism Failure
