SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2026-21715

As a result, code running under `--permission` with restricted `--allow-fs-read` can still use `fs.realpathSync.native()` to check file existence, resolve symlink targets, and enumerate filesystem paths outside of permitted directories.

LOW 3.3EPSS 0.16%

Does this matter?

Lower severity and a low EPSS score (0.16%). Track it; it rarely justifies an emergency change on its own.

Description

A flaw in Node.js Permission Model filesystem enforcement leaves `fs.realpathSync.native()` without the required read permission checks, while all comparable filesystem functions correctly enforce them. As a result, code running under `--permission` with restricted `--allow-fs-read` can still use `fs.realpathSync.native()` to check file existence, resolve symlink targets, and enumerate filesystem paths outside of permitted directories. This vulnerability affects **20.x, 22.x, 24.x, and 25.x** processes using the Permission Model where `--allow-fs-read` is intentionally restricted.

CVSS 3.0
3.3 LOWCVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
EPSS
0.16% probability · 5th percentile
CISA KEV
Not listed
Weakness
CWE-732
Affected
nodejs/node.js
Source
support@hackerone.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.