CVE-2026-107162

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.

CVSS v3 6.8 MEDIUM

6.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.6 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
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://github.com/ExpressGateway/express-gateway/issues/1076
https://www.vulncheck.com/advisories/express-gateway-through-1.16.11-oauth-2.0-refresh-token-validation-bypass
https://github.com/ExpressGateway/express-gateway/issues/1076

Configurations

No configuration.

History

10 Oct 2026, 03:17

Type	Values Removed	Values Added
References	~~() https://github.com/ExpressGateway/express-gateway/issues/1076 -~~	() https://github.com/ExpressGateway/express-gateway/issues/1076 -

07 Oct 2026, 13:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-07 13:17

Updated : 2026-10-10 03:17

NVD link : CVE-2026-107162

Mitre link : CVE-2026-107162

CVE.ORG link : CVE-2026-107162

JSON object : View

Products Affected

No product.

CWE

CWE-287

Improper Authentication

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