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@fastify/oauth2 vulnerable to Login CSRF via OAuth state cookie not cleared after callback

Type: advisorySource: Official CVE List1 source record

@fastify/oauth2 is a Fastify wrapper for OAuth2 login flows. In versions 7.2.0 through 8.3.1, the state and code-verifier cookies are set without a Path attribute at a login route with two or more path segments, while the clearing step at the OAuth callback writes them with a root path, so the original cookies survive the callback and the documented single-use guarantee for the state value does not hold. A state value an attacker learns stays valid for the rest of the browser session, letting the attacker drive their own authorization flow in the victim's browser and sign the victim in to the attacker's account (login CSRF). The issue is fixed in @fastify/oauth2 8.3.2, and users should upgrade to 8.3.2 or later. As a workaround, set an explicit cookie path so the set and the clear name the same cookie.

Announced Source revision 1
Original source ↗

CVE-2026-110008

Primary source · Revision 1

Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.

Security context

Source reference: cve:CVE-2026-110008

@fastify/oauth2

Source reference: /containers/cna/affected/0/product

Affected versions
Not stated in this record
Fixed versions
Not stated in this record
Prerequisites
Not stated in this record

Structured affected-version data

Original package identities and version rules from this source.

[
  {
    "vendor": "@fastify/oauth2",
    "product": "@fastify/oauth2",
    "versions": [
      {
        "status": "affected",
        "version": "7.2.0",
        "lessThan": "8.3.2",
        "versionType": "semver"
      },
      {
        "status": "unaffected",
        "version": "8.3.2",
        "versionType": "semver"
      }
    ],
    "packageURL": "pkg:npm/@fastify/oauth2",
    "defaultStatus": "unaffected"
  }
]
Related CVEs
CVE-2026-110008

Source reference: /cveMetadata/cveId

Publisher severity

medium

Source reference: /containers/cna/metrics

Event
#38881 · Revision 1
Added to Heist Feed
Publisher date
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