Vulnerability from bitnami_vulndb
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": [
{
"package": {
"ecosystem": "Bitnami",
"name": "node",
"purl": "pkg:bitnami/node"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "20.20.2"
},
{
"introduced": "21.0.0"
},
{
"fixed": "22.22.2"
},
{
"introduced": "23.0.0"
},
{
"fixed": "24.14.1"
},
{
"introduced": "25.0.0"
},
{
"fixed": "25.8.2"
}
],
"type": "SEMVER"
}
],
"severity": [
{
"score": "CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N",
"type": "CVSS_V3"
}
]
}
],
"aliases": [
"CVE-2026-21713"
],
"database_specific": {
"cpes": [
"cpe:2.3:a:nodejs:node.js:*:*:*:*:*:*:*:*"
],
"severity": "Medium"
},
"details": "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.\r\n\r\nNode.js already provides timing-safe comparison primitives used elsewhere in the codebase, indicating this is an oversight rather than an intentional design decision.\r\n\r\nThis vulnerability affects **20.x, 22.x, 24.x, and 25.x**.",
"id": "BIT-node-2026-21713",
"modified": "2026-09-08T08:34:36.952Z",
"published": "2026-04-06T07:58:36.353Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nodejs.org/en/blog/vulnerability/march-2026-security-releases"
},
{
"type": "WEB",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-21713"
}
],
"schema_version": "1.6.2"
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
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- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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