CVE-2024-21896

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-02-20 · updated 2026-06-17
Weakness: CWE-27

Description

The permission model protects itself against path traversal attacks by calling path.resolve() on any paths given by the user. If the path is to be treated as a Buffer, the implementation uses Buffer.from() to obtain a Buffer from the result of path.resolve(). By monkey-patching Buffer internals, namely, Buffer.prototype.utf8Write, the application can modify the result of path.resolve(), which leads to a path traversal vulnerability. This vulnerability affects all users using the experimental permission model in Node.js 20 and Node.js 21. Please note that at the time this CVE was issued, the permission model is an experimental feature of Node.js.

Affected products

Node.js: from 20.0.0 before 20.11.1; from 21.0.0 before 21.6.2 — fixed in 20.11.1, 21.6.2

How to fix

Upgrade to a fixed version: Node.js 20.11.1, 21.6.2. Check the vendor advisory for mitigations.

References

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