{"id":"CVE-2026-93603","title":"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.…","summary":"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.…","severity":"critical","cvss":10,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","cwe":["CWE-94"],"vendor":"patriksimek","product":"vm2","affected":["vm2 < 3.12.1"],"published":"2026-09-18","updated":"2026-09-22","sourceUpdated":"2026-09-22T15:17:24.040","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-93603","references":[{"url":"https://github.com/patriksimek/vm2/security/advisories/GHSA-j89j-5m6r-cr2q","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/vm2-before-3.12.1-sandbox-escape-rce-via-non-strict-host-function","label":"disclosure@vulncheck.com"},{"url":"https://github.com/patriksimek/vm2/security/advisories/GHSA-j89j-5m6r-cr2q","label":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"tags":["nvd","cve.org","exploit-available"],"epss":0.00726,"epssPercentile":0.52057,"exploitAvailable":true,"ssvc":{"exploitation":"poc","automatable":"yes","technicalImpact":"total","timestamp":"2026-09-22T14:25:04.925932Z"},"ingestedAt":"2026-09-18T13:41:41.662Z","slug":"CVE-2026-93603","body":"## Overview\n\nvm2 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.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"abyssal","depthScore":67,"depthScoreParts":{"impact":55,"likelihood":0.1,"exploitation":12,"ransomware":0},"changes":[{"seq":209097,"id":"CVE-2026-93603","ts":1790089537451,"field":"exploit_available","old":"false","new":"true"}]}