CVE-2026-41213

@node-oauth/oauth2-server is a module for implementing an OAuth2 server in Node.js. The token exchange path accepts RFC7636-invalid code_verifier values (including one-character strings) for S256 PKCE flows. Because short/weak verifiers are accepted and failed verifier attempts do not consume the authorization code, an attacker who intercepts an authorization code can brute-force code_verifier guesses online until token issuance succeeds.

CVSS v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/node-oauth/node-oauth2-server/security/advisories/GHSA-jhm7-29pj-4xvf	Exploit Mitigation Vendor Advisory
https://github.com/node-oauth/node-oauth2-server/security/advisories/GHSA-jhm7-29pj-4xvf	Exploit Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:node-oauth:node-oauth\/oauth2-server:*:*:*:*:*:node.js:*:*

History

26 Oct 2026, 21:10

Type	Values Removed	Values Added
Summary		(es) @node-oauth/oauth2-server es un módulo para implementar un servidor OAuth2 en Node.js. La ruta de intercambio de tokens acepta valores de code_verifier inválidos según RFC7636 (incluyendo cadenas de un solo carácter) para flujos PKCE S256. Debido a que se aceptan verificadores cortos/débiles y los intentos fallidos de verificador no consumen el código de autorización, un atacante que intercepta un código de autorización puede forzar por fuerza bruta suposiciones de code_verifier en línea hasta que la emisión del token tenga éxito.

Information

Published : 2026-04-23 19:17

Updated : 2026-10-26 21:10

NVD link : CVE-2026-41213

Mitre link : CVE-2026-41213

CVE.ORG link : CVE-2026-41213

JSON object : View

Products Affected

node-oauth

node-oauth\/oauth2-server

CWE

CWE-307

Improper Restriction of Excessive Authentication Attempts

CWE-1289

Improper Validation of Unsafe Equivalence in Input

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