CVE-2026-21716: An incomplete fix for CVE-2024-36137 leaves `FileHandle.chmod()` and `FileHandle.chown()` in the promises API

Routine

LOW 3.3UPGRADE

CVE-2026-21716 is a low-severity flaw (CVSS 3.3) affecting node.js. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

An incomplete fix for CVE-2024-36137 leaves `FileHandle.chmod()` and `FileHandle.chown()` in the promises API without the required permission checks, while their callback-based equivalents (`fs.fchmod()`, `fs.fchown()`) were correctly patched. As a result, code running under `--permission` with restricted `--allow-fs-write` can still use promise-based `FileHandle` methods to modify file permissions and ownership on already-open file descriptor

Why this priority

No elevated risk signals yet

A fixed release or distro patch exists.

Risk facts

CVSS score	3.3 (Low)
Attack vector	Local
Attack complexity	Low
Privileges needed	Low
User interaction	None
EPSS exploit chance	0.1% (top 97%)
CISA exploited list	No
Weakness	CWE-862
Published	2026-03-30
Last modified	2026-08-19

Publisher (CNA): HackerOne · Vendor: nodejs

Last updated 2026-08-19 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-03-30 20:16 UTCPublished CVE record published
2026-08-19 13:18 UTCUpdated Record last modified

nodejs node.js UPGRADE

Affected: <= 20.20.1 · >= 22.0.0 and <= 22.22.1 · >= 24.0.0 and <= 24.14.0 · >= 25.0.0 and <= 25.8.1

Fixed in: newer than 25.8.1

Safe to downgrade to: a release before 22.0.0

1. Check installed version

apt-cache policy node.js || rpm -q node.js || node.js --version

2. UPGRADE to newer than 25.8.1 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade node.js

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade node.js

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

3. If no update is available yet, DOWNGRADE to a release before 22.0.0 (Debian / Ubuntu)

apt-cache madison node.js sudo apt install node.js=<VERSION_BEFORE_22.0.0> sudo apt-mark hold node.js

3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list node.js sudo dnf downgrade node.js-<VERSION_BEFORE_22.0.0> sudo dnf versionlock add node.js

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-21716?

node.js: upgrade to newer than 25.8.1. Exact commands for each OS are on this page.

Is CVE-2026-21716 being exploited?

CVE-2026-21716 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-21716 affect?

CVE-2026-21716 affects node.js. Severity is low (CVSS 3.3). An incomplete fix for CVE-2024-36137 leaves `FileHandle.chmod()` and `FileHandle.chown()` in the promises API without the required permission checks, while their callback-based equivalents (`fs.fchmod()`, `fs.fchown()`) were correctly patch

How urgent is CVE-2026-21716?

Priority 12/100. No elevated risk signals yet.

Software pages

Node.js vulnerabilities

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References

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