CVE-2026-21713_CVE-2026-21713

5.9 / 10

MEDIUM

CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

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**.

Basic Information

ID CVE-2026-21713

Source hackerone

Published Mar 30, 2026 at 19:07

Modified Mar 30, 2026 at 19:45

Affected Product

Vendor nodejs

Product node

Version 20.20.1

Affected Versions nodejs node 20.20.1
nodejs node 22.22.1
nodejs node 24.14.0
nodejs node 25.8.1
nodejs node 4.0
nodejs node 5.0
nodejs node 6.0
nodejs node 7.0
nodejs node 8.0
nodejs node 9.0
nodejs node 10.0
nodejs node 11.0
nodejs node 12.0
nodejs node 13.0
nodejs node 14.0
nodejs node 15.0
nodejs node 16.0
nodejs node 17.0
nodejs node 18.0
nodejs node 19.0

References

nodejs.org /en/blog/vulnerability/march-2026-security-releases

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Description

Basic Information

Affected Product

References

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