Express Gateway through 1.16.11 OAuth 2.0 Refresh Token Validation Bypass (ExpressGateway express-gateway)
At a glance
- Source
- NVD
- EPSS
- EPSS 0.36 % · percentile 30 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- VulnCheck
- NVD status
- Awaiting Analysis
Description
Express Gateway through 1.16.11 contains an authentication bypass vulnerability in the OAuth 2.0 refresh_token grant that fails to validate the token secret or issuing client. Attackers with any valid client credentials and the identifier portion of another user's refresh token can obtain that user's access token and impersonate them against oauth2-protected APIs.
Weaknesses (CWE)
- CWE-287 — Improper Authentication
References
- https://github.com/ExpressGateway/express-gateway/issues/1076
- https://github.com/ExpressGateway/express-gateway
- https://github.com/ExpressGateway/express-gateway/blob/45612814d12f65889ef3bdf80b2ed7ab9b557736/lib/policies/oauth2/oauth2-server.js#L221-L247
- https://github.com/ExpressGateway/express-gateway/blob/45612814d12f65889ef3bdf80b2ed7ab9b557736/lib/services/tokens/token.service.js#L100-L136
- https://www.vulncheck.com/advisories/express-gateway-through-1.16.11-oauth-2.0-refresh-token-validation-bypass
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 4.0 | HIGH 7.6 | CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N | VulnCheck |
| CVSS 3.1 | MEDIUM 6.8 | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N | VulnCheck |
| CVSS 4.0 | HIGH 7.6 | CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X | NVD · disclosure@vulncheck.com (Secondary) |
| CVSS 3.1 | MEDIUM 6.8 | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N | NVD · disclosure@vulncheck.com (Secondary) |
European references
- ENISA EUVD · EUVD-2026-94316
- GCVE · GCVE-0-2026-107162
Affected products
| Product | Versions |
|---|---|
| ExpressGateway · express-gateway | affected 0 ≤ 1.16.11 |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |