CVE-2021-21413

HIGH8.0EPSS 0.14%

Misuse of `Reference` and other transferable APIs may lead to access to nodejs isolate

Published: 4/6/2021Modified: 3/13/2026
Also known as:GHSA-mmhj-4w6j-76h7

Description

Versions of `isolated-vm` before v4.0.0, and especially before v3.0.0, 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. To address these issues the following changes were made in v4.0.0: - Documentation was updated with more explicit guidelines on building secure applications. - `Reference` instances will no longer follow prototype chains by default, nor will they invoke accessors or proxies. - All `isolated-vm` API prototypes are now immutable. - `NativeModule` constructor may only be invoked from a nodejs isolate.

Affected packages (1)

CVSS scores

SourceVersionSeverityVector
osvCVSS 3.1HIGH8.0CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N

References (5)