{"id":"CVE-2026-93603","published":"2026-09-18T14:19:12.003","lastModified":"2026-09-22T15:17:24.040","description":"vm2 through 3.12.0 (fixed in 3.12.1) does not correctly handle a nullish `this` receiver in the apply trap of its bridge (lib/bridge.js): when sandboxed code calls a host-provided non-strict (sloppy-mode) function without a receiver — e.g. `fn()`, a detached method, `fn.call()`, `fn.apply(undefined)`, `Reflect.apply(fn, undefined, [])`, or `fn.bind()()` — the undefined receiver is passed straight through to the host call, and V8 substitutes the host realm's global object for `this`. vm2 then wraps and returns that object to the sandbox, giving sandboxed script a live proxy of the host global. This allows a complete sandbox escape: untrusted script can reach `process` and execute arbitrary code/commands on the host (for example via `process.getBuiltinModule('child_process').execSync`). Exploitation requires that the embedding application expose at least one non-strict host function to the sandbox; strict-mode and ES module host functions are not affected.","cvssScore":10,"cvssSeverity":"CRITICAL","cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","cwes":["CWE-94"],"vendors":[],"products":[],"references":[{"url":"https://github.com/patriksimek/vm2/security/advisories/GHSA-j89j-5m6r-cr2q","tags":[]},{"url":"https://www.vulncheck.com/advisories/vm2-before-3.12.1-sandbox-escape-rce-via-non-strict-host-function","tags":[]},{"url":"https://github.com/patriksimek/vm2/security/advisories/GHSA-j89j-5m6r-cr2q","tags":[]}],"exploitRefs":[{"url":"https://github.com/patriksimek/vm2/security/advisories/GHSA-j89j-5m6r-cr2q","tags":[]},{"url":"https://github.com/patriksimek/vm2/security/advisories/GHSA-j89j-5m6r-cr2q","tags":[]}],"hasPoc":true,"ai":{"summary":"The flaw allows untrusted code to escape a sandbox and execute arbitrary code on the host system by calling non-strict functions with an undefined receiver, leading to Remote Code Execution (RCE).","exploitability":"Exploitation is moderately hard as it requires the embedding application to expose at least one non-strict host function to the sandbox.","blast_radius":"If exploited, this vulnerability could lead to complete compromise of the host system, including execution of arbitrary commands via the `process` object.","remediation":"Upgrade to vm2 version 3.12.1 or later.","detection":"No reliable host or network indicator is derivable from the published description.","tags":["rce","sandbox-escape","vm2"],"model":"qwen2.5:7b-instruct","analyzedAt":"2026-09-27T08:55:20.097Z"}}