CVE-2026-21713: nodejs vulnerability
nodejs · node
Vendor fix available · Affected: nodejs · Exploitation: unlikely (under 1%)
Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.
Higher than 30% of scored CVEs
DescriptionCVE.org
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.
Affected products1
From the CVE record. A product or version that is not listed is unknown, not unaffected.
- nodejs · nodefrom 20.20.1 up to and including 20.20.1; from 22.22.1 up to and including 22.22.1; from 24.14.0 up to and including 24.14.0; from 25.8.1 up to and including 25.8.1; from 4.0 before 4.*; from 5.0 before 5.* and 14 more
On the Atlas
Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.
- Exploitation
- Unlikely (under 1%). EPSS under 1%, or no score yet.
- CISA KEV
- Not listed
- Public check
- No public nuclei template
- Vendor
- nodejs
- Published
- March 2026
- Bounty reports
- 1 disclosed on HackerOne
Disclosed bug bounty reports about CVE-2026-21713
The reports on HackerOne that name this CVE, with HackerOne's own outcome. Titles and metadata only.
- Timing side-channel in HMAC verification via memcmp() in crypto_hmac.cc leads to potential MAC forgeryNode.js · 2026 · medium severityValid
CoverageNo articles yet
No CyberSIXT article names CVE-2026-21713 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.