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Duplicate Advisory: `allowAsync: false` can be bypassed through Promise thenable assimilation in VM and NodeVM

Type: withdrawalSource: OSV1 source record

## Duplicate Advisory This advisory has been withdrawn because it is a duplicate of GHSA-f8gf-w286-fmq2. This link is maintained to preserve external references. ## Original 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.

Announced Source revision 1
Original source ↗

GHSA-9538-79j2-h62h

Primary source · Revision 1 · Withdrawn

Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.

Security context

Source reference: osv:GHSA-9538-79j2-h62h

vm2

Source reference: /affected/0/package/name

Affected versions
Not stated in this record
Fixed versions
Not stated in this record
Prerequisites
Not stated in this record

Structured affected-version data

Original package identities and version rules from this source.

[
  {
    "ranges": [
      {
        "type": "SEMVER",
        "events": [
          {
            "introduced": "0"
          },
          {
            "last_affected": "3.11.7"
          }
        ]
      }
    ],
    "package": {
      "name": "vm2",
      "purl": "pkg:npm/vm2",
      "ecosystem": "npm"
    },
    "database_specific": {
      "source": "https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/09/GHSA-9538-79j2-h62h/GHSA-9538-79j2-h62h.json"
    }
  }
]

Publisher severity

high

Source reference: /database_specific/severity

Event
#85857 · Revision 1
Added to Heist Feed
Publisher date
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