# CVE-2026-21713: Information disclosure in node

> Attackers can exploit a timing side-channel in Node.js HMAC verification to infer signature values, potentially compromising authentication integrity.

- **Severity:** Medium 5.9 (`CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 30 Mar 2026
- **Updated:** 10 May 2026
- **Also known as:** ALPINE-CVE-2026-21713, AZL-81242, AZL-81248, BELL-CVE-2026-21713, BIT-node-2026-21713, BIT-node-min-2026-21713, CLEANSTART-2026-NP94260, DEBIAN-CVE-2026-21713, GHSA-6r7g-3mm3-fhw7, MINI-5m45-3fv3-rpph, MINI-5vmg-c4pg-wxvh, MINI-676p-56mf-w5j9, MINI-8mg6-fvq7-7hm3, MINI-92q8-8vvh-vrqr, MINI-ccvq-wpv6-7cq2, MINI-frph-59pj-r7j8, UBUNTU-CVE-2026-21713

## What is CVE-2026-21713?

CVE-2026-21713 is a medium-severity vulnerability in Nodejs Node.js, published on 30 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A flaw in Node.js HMAC verification uses a non-constant-time comparison when validating user-provided signatures, potentially leaking timing information proportional to the number of matching bytes. Under certain threat models where high-resolution timing measurements are possible, this behavior could be exploited as a timing oracle to infer HMAC values.

Node.js already provides timing-safe comparison primitives used elsewhere in the codebase, indicating this is an oversight rather than an intentional design decision.

This vulnerability affects **20.x, 22.x, 24.x, and 25.x**.

Weakness: CWE-208 (Observable Timing Discrepancy)

## Which versions are affected by CVE-2026-21713?

2 open source packages ship an affected version, including node and node-min. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `node` | Bitnami | All versions | 20.20.2, 22.22.2, 24.14.1, 25.8.2 |
| `node-min` | Bitnami | All versions | 20.20.2, 22.22.2, 24.14.1, 25.8.2 |

Products: Nodejs Node.js.

## How do I fix CVE-2026-21713?

Upgrade node to a fixed version for your release line: 20.20.2, 22.22.2, 24.14.1 or 25.8.2.

## Is CVE-2026-21713 being exploited?

There is no known exploitation of CVE-2026-21713 in the wild and no public exploit code.

## Other vulnerabilities in Nodejs Node.js

- [CVE-2023-32002](https://insights.sbomify.com/CVE-2023-32002/): Security feature bypass in Node (critical 9.8)
- [CVE-2016-6303](https://insights.sbomify.com/CVE-2016-6303/): Integer overflow in n/a (critical 9.8)
- [CVE-2017-15896](https://insights.sbomify.com/CVE-2017-15896/): Security feature bypass in Node.js (critical 9.1)
- [CVE-2018-7160](https://insights.sbomify.com/CVE-2018-7160/): Server-side request forgery in Node.js (high 8.8)
- [CVE-2018-12120](https://insights.sbomify.com/CVE-2018-12120/): Misconfiguration in Node.js (high 8.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-21713 and fix it if it is affected.

What it is: CVE-2026-21713 is a medium-severity vulnerability in Nodejs Node.js, published on 30 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-21713 in the wild and no public exploit code.

Affected packages and fixed versions:
- node (Bitnami): affected all versions; fixed in 20.20.2, 22.22.2, 24.14.1, 25.8.2
- node-min (Bitnami): affected all versions; fixed in 20.20.2, 22.22.2, 24.14.1, 25.8.2

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-21713/ (Markdown: https://insights.sbomify.com/CVE-2026-21713/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-21713
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-21713
- OSV: https://osv.dev/vulnerability/CVE-2026-21713

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-21713/
Summaries are generated and may contain mistakes; the official description above is the record.