CVE-2026-21713

medium Red Hat
CVSS v3 Base Score
5.9
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
EPSS Score
0.0%
Exploitation probability in 30 days
Top 98% most likely to be exploited
Attack Characteristics
Attack Vector
Network
Attack Complexity
High
Privileges Required
None
User Interaction
None
Confidentiality
High
Integrity
None
Availability
None
Published: March 30, 2026 (102 days ago)
Last Modified: March 30, 2026
Vendor: Red Hat
Fix Available: ✓ Yes
Source: REDHAT

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**.

CWE

CWE-208

Affected Products

Red Hat Enterprise Linux 10Red Hat Enterprise Linux 8Red Hat Enterprise Linux 9

Fix Status

✅ Fix Available

References

🔗 bugzilla.redhat.com 🔗 www.cve.org 🔗 nvd.nist.gov 🔗 nodejs.org