{"id":"CVE-2021-21413","url":"https://www.cyber-defence.io/tools/cve/CVE-2021-21413","generatedAt":"2026-10-27T23:36:33.704Z","title":"Versions of isolated-vm before v4.0.0 have API pitfalls which may make it easy for implementers to expose supposed secure isolates to the permissions of the main nodejs isolate.","description":"isolated-vm is a library for nodejs which gives you access to v8's Isolate interface. Versions of isolated-vm before v4.0.0 have API pitfalls which may make it easy for implementers to expose supposed secure isolates to the permissions of the main nodejs isolate. Reference objects allow access to the underlying reference's full prototype chain. In an environment where the implementer has exposed a Reference instance to an attacker they would be able to use it to acquire a Reference to the nodejs context's Function object. Similar application-specific attacks could be possible by modifying the local prototype of other API objects. Access to NativeModule objects could allow an attacker to load and run native code from anywhere on the filesystem. If combined with, for example, a file upload API this would allow for arbitrary code execution. This is addressed in v4.0.0 through a series of related changes.","published":"2021-03-30T23:15:14.000Z","lastModified":"2026-06-17T03:35:32.000Z","status":"Modified","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"3.1","score":9.6,"severity":"CRITICAL","vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H"},"cwe":["CWE-913"],"affected":["isolated-vm project/isolated-vm"],"epss":{"score":0.00719,"percentile":0.5362,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.72%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://github.com/laverdet/isolated-vm/blob/main/CHANGELOG.md#v400","tags":["Release Notes","Third Party Advisory"],"source":"security-advisories@github.com"},{"url":"https://github.com/laverdet/isolated-vm/commit/2646e6c1558bac66285daeab54c7d490ed332b15","tags":["Patch","Third Party Advisory"],"source":"security-advisories@github.com"},{"url":"https://github.com/laverdet/isolated-vm/commit/27151bfecc260e96714443613880e3b2e6596704","tags":["Patch","Third Party Advisory"],"source":"security-advisories@github.com"},{"url":"https://github.com/laverdet/isolated-vm/security/advisories/GHSA-mmhj-4w6j-76h7","tags":["Third Party Advisory"],"source":"security-advisories@github.com"},{"url":"https://github.com/laverdet/isolated-vm/blob/main/CHANGELOG.md#v400","tags":["Release Notes","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/laverdet/isolated-vm/commit/2646e6c1558bac66285daeab54c7d490ed332b15","tags":["Patch","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/laverdet/isolated-vm/commit/27151bfecc260e96714443613880e3b2e6596704","tags":["Patch","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/laverdet/isolated-vm/security/advisories/GHSA-mmhj-4w6j-76h7","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2021-21413","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}